A Decentralized Real Estate Data Exchange & Real Estate Transaction Application
Rex: referring to the platform, Rex REX: referring to the token, REX
Real property, defined as anything owned by a person or entity in regard to land, real estate, the
improvements on it, or the right to use or inhabit it, has existed at least since man first settled
the ancient lands of Mesopotamia in 4500 BCE. Real estate—the transaction of value assigned
to land and living space—is one of the oldest and most essential industries in the world. Almost
every single human being relies on it for their most basic needs. Since the time of those early
settlements, there have been two major pillars of a real estate transactions that also constitute
the focal point of the Rex ecosystem:
For decades leading up to the digital revolution, obtaining reliable property information remained
difficult. Today, with advances in technology, data has become easier to create and transmit
across industries. However, in the world of real estate, data is still highly controlled, poorly
maintained, and governed by centralized organizations. This results in exorbitant transaction
and listing fees, and data walled into silos that are not interoperable within the fragmented
global real estate industry ecosystem.
Rex believes the real estate industry is ready to move beyond traditional closed storage
systems, where its value is limited to the interest of the entity controlling it. Rex envisions a
world of shared information, where individuals can monetize and realize the true value of their
data, and it isn’t limited by central barriers.
Rex will begin by building a global real estate data exchange, an information layer that is
accessible to everyone. The database will minimize listing fees and maximize listing exposure. It
will eliminate spam through community participation. It will provide incentive-based curation
registries that will open up new data channels. In later phases, Rex will introduce programmable
data escrow contracts, a way to efficiently manage transaction documentation, communication
Rex can be thought of in two ways:
Firstly: a global listing portal in which users own and control their data, and have access to a
global ecosystem of information.
Second: A user-curated real estate marketplace. It’s analogous to Wikipedia (user-curated
information) meets Amazon (global marketplace). Atop that, users who curate data earn
rewards for their participation.
Groundbreaking recent advances in peer-to-peer data distribution and blockchain technology
give Rex the ability to provide universal access to real estate information via a digital
marketplace, and streamline the transaction process.
1.1 What is a Listing Portal?
A listing portal acts as a platform for the orderly correlation and dissemination of listing
information to better serve brokers’ clients, landlords, tenants, and the public. A listing portal is a
suite of services that enables real estate brokers, landlords and sellers to establish contractual
offers of compensation, that facilitates cooperation with other transaction participants, and that
accumulates and distributes listing information.
1.2 Evolution of a Listing Portal
Listing Service 1.0 (Pre-Internet)
Pre-internet, the real estate industry relied on print for dependable real estate information. Print
releases were bi-annual with dated property information.
Listing Service 2.0 (Post-Internet, Pre-Blockchain)
Most countries have a handful of dominant online listing portals.
Listing fees vary world-wide. We’ll provide one example in the United States:
We can approximate that the average subscriber is paying at least $30.00/listing per month, or $360.00/listing per year:
300/10 = 30
30 * 12 = 360
Users subscribing to platinum services pay an estimated increase of approximately $520.00/listing per month or $6,240.00/listing per year:
30+ 400 + 90 = 520.00
520 * 12 = 6,240.00
Common complaints include a lack of price transparency, poor user experience, and an excess of stale information.
Internal Solutions (That Lead to More Problems )
Due to cost and the lack of database interoperability, firms began developing their own portal systems. This proved counterproductive and widened the gap of incongruity.
1.3 Listing Portal 3.0: Overview of Rex’s Data Exchange
Rex provides a new type of listing portal, one where data is collected, shared and accessible to
all participants. Rex's shared database (RexIndexer) is decentralized by nature, with firms
running independent REX nodes that give them the ability to store data locally and tap into the
wider ecosystem—offering both internal and external functionality. The REX node is a
combination of the RexIndexer, Ethereum and IPFS nodes.
The value to the firm includes ownership, control and portability of their data, access to new
curation feeds, spam reduction, and reward systems that compensate users for participating in
the network. For every listing not marked as spam by other community members (see Rex’s
Spam Registry below) the Listing Rewards Contract pays the user in REX tokens. Fees incurred
on REX are recirculated back into the Listing Rewards Contract fueling a perpetual cycle of fees
Traditional listing portals generate revenue from collecting user data and charging high
subscription fees to publish to their platform. The user delivers value (through providing data),
but the listing portal is the financial beneficiary. On Rex, listing fees are nominal ($0.10-$0.20
per listing). This fee is enacted to fund the mitigation of spam. The more listings a user
publishes that are not marked spam (see Spam Registry below), the more REX rewards they
earn. The more listings on Rex, the more eyeballs. The more eyeballs, the more demand for the
Value is initially driven by listors, and they are the beneficiaries with cheaper, cleaner data. In
addition, they, and other users, can monetize their data through an open marketplace that
includes market studies, inspection reports, appraisals, and advertising space. Listing exposure
will go from regionally siloed and benefitting a few, to globally accessible, locally sourced,
comprised of more reliable data and available with richer data sets, rendering Rex one large,
homogenous database that is not bound by countries or borders.
1.4 Why Rex is Starting with Listings
Smart contracts provide a groundbreaking way to transact real estate. They offer the real estate
industry the ability to transact property faster, cheaper, and more securely. However, the
industry cannot successfully take full advantage of the technology until existing infrastructure
problems are addressed.
One major issue is universal property identification. This is why Rex is starting with listings.
First, the RexIndexer, with its open-access design, creates the interoperability layer between
REX nodes. The RexIndexer gives firms, brokers and companies alike the ability to own,
maintain and share real estate information quickly and easily. Second, it provides an opportunity
to create a global property identification system that is not owned or controlled by a centralized
organization. This is a pivotal step toward later enacting transaction processes.
The Ethereum ecosystem has already laid much of the groundwork of establishing a safe,
secure network on a global scale. Rex—and entire the real estate industry—can capitalize on
this infrastructure by building the universal property ID layer. The property identifier can later be
used for title, firms, brokers, lending, insurance and technology companies to search, track and
transact property. Once the property ID system is established, the industry can effectively
engage in smart transactions.
By starting with listing data, Rex can automatically give each property a unique ID. This ID is
open source and accessible to anyone, anytime for free, and creates the ideal basis upon which
to create a functional and deep ecosystem.
Rex envisions a 3-year timeframe to deploy our initial mission:
Phase 1: Pilot: Listing Portal & Property Identification, Data Exchange, Curation Registries
Phase 2: Scaling
Phase 3: Transactions: Escrow Contracts
Rex’s roadmap takes into account the current immaturity of the Ethereum ecosystem, increasing
government participation and the time, education and experimentation required to attract and
Blockchain technology is in its infancy. The basic infrastructure is still being built and tested.
Thus, REX will focus the first 12 months launching our Pilot Program in a few test markets. The
Pilot will consist of participants exchanging data through the RexIndexer. During this period,
Rex will introduce and test its Spam Registry which is modeled after AdChains Token Curated
Registries https://medium.com/@ilovebagels/token-curated-registries-1-0-61a232f8dac7 .
We recently began our go to market strategy, focusing on a top-down bottom-up approach. We
met with several major firms and many more brokers to gain feedback on our existing alpha.
REX will gradually on board users during the Pilot through a series of digital campaigns,
conferences, speaking engagements and canvassing.
1.5 Transactions: Escrowing Data
A major flaw often encountered in the real estate transaction process is miscommunication
between participating parties. There are various types of documentation that must be produced
during the transaction process, and the path of these deliverables often takes circuitous routes.
Documents include credit reports, bank statements, insurance estoppels, government
identification, inspection reports, survey data and many other types of sensitive information.
Typically, these requests are coming from attorney’s, lenders, brokers and insurance
In transit, these documents often take several email steps before reaching their destination, and
it is difficult for transaction participants to accurately track documentation collection. In addition
to a poor tracking system, the buyer/seller/lessor/lessee risks their data being released through
the carelessness of one of the transaction participants.
Rex will offer, via its application layer, an escrow service that will mitigate future security leaks
and provide an efficient and reliable mechanism to track information flow. On the transactions
page, users can create document lists, designating which participant is responsible for
producing which document. All transaction participants will upload their documents via Rex’s
Data Escrow Contract. The documents flowing through Rex’s Data Escrow Contract will be
encrypted and stored via IPFS.
The contract will produce a private key that the uploading participant can distribute to other
transaction participants. Transaction participants can track in real time what documents have
been collected and what data still needs to be produced. This process will create an open
transparent layer that securely tracks sensitive information. Rex’s Data Escrow Contracts will
eventually have the ability to escrow deposits, payments and allowances.
2.1 What is the Blockchain?
The blockchain is a distributed database or public ledger that gained popularity following the
release of Bitcoin. It maintains a continuously growing list of all the transactions in a particular
network that have ever been executed. The “blocks” are added in chronological order with
cryptography to prevent tampering, thus becoming an indelible record of every transaction in the
network and accessible to every participant .
2.2 What is Ethereum?
The Ethereum system can be described as a single shared computer that is run by the network
of users, on which resources are parceled out and paid for in Ether. In essence, it’s a world
2.3 Why is Rex building on Ethereum?
Data needs to be on a server. A server is generally owned or leased by a corporation.Therefore,
the individual relinquishes control of their data. This leads to increased costs with low
accessibility and virtually no interoperability between systems.
We now have the means of decentralizing data. BitTorrent, Swarm, and IPFS can do that on
their own, but the blockchain provides the ability to organize and order the data with no central
authority. Ethereum provides a means to mesh together the blockchain, data distribution, and
currency all under one roof. Ether, which is the medium used to transact on the Ethereum
Blockchain, can be exchanged for REX, and REX will fuel the application. This is the absolute
value Rex sees for blockchain and Ethereum technology.
Rex is building on the Ethereum protocol for several reasons. The first is to provide a distributed
database where anyone can access real estate information for free.
Distributed databases provide two advantages:
1. The user always owns and has access to their information. Third party advertisements,
especially those of competing brokers, will never exist on a listees page unless they
initiate private advertising.
2. Price Stability: No central authority owns the information, eliminating capital controls on the
Ethereum also provides a means for tokenized currency. Rex is utilizing the tokenized aspect of
Ethereum to reward contributors for providing and curating content while offering a digital
exchange where real estate data can be freely traded.
While Rex's database stores all active listings for 90 days, it is possible to build a
comprehensive history of each individual parcel ever listed on the platform.
2.4 Data Distribution
Since the 1990’s, the HTTP protocol has been a useful tool to send and receive data packets
from one or more central servers to the requesting node.
Today, we distribute much larger packets of information. If too many requests are made servers
become overwhelmed. The result is increased latency, downtime, and maintenance
requirements. The costs are passed from owner to user. In 2017, the HTTP protocol is
inefficient. We’re at an inflection point where not all nodes need to communicate through
centralized routes, but rather, can do so peer-to-peer.
The Interplanetary File System (IPFS) is a new hypermedia distribution protocol, addressed by
content and identities. IPFS enables the creation of completely distributed applications. It aims
to make the web faster, safer, and more open.
2.6 Benefits to Rex
IPFS provides a means for Rex to distribute real estate data in a decentralized manner. When a
listing or transaction documents are submitted to Rex, Rex hashes the data and pushes the
content to IPFS. The data is encrypted and disseminated globally to machines running the IPFS
instance. Since the data is distributed and not stored on one single computer, costs are reduced
and access is universal. The architecture of IPFS provides a built in governor so Rex (or any
other applications built on top of Rex) cannot charge large sums of money or deny access to
Reed Hastings built Netflix with the idea of streamlining the way users view and receive digital
content. First, Hastings exercised value out of the existing technological infrastructure. Users
rented DVDs online and had them physically delivered via US mail, thus avoiding the
inconveniences of traditional retail (time, travel, and late fees). Netflix grew exponentially as
infrastructure matured and delivery went from physical to digital.
Rex is taking a similar long-term approach. Starting with the foundation laid by Ethereum, Rex
will begin assembling the shared database and opening up the data exchange through User
Curated Registries. As the database scales and the network stabilizes, Rex will introduce data
escrow services that will secure documentation sharing and provide the ability to store deposits,
payments and allowances.
The Pilot will be focused in 2-4 markets. Over the 12 month period, Rex will release the
Universal Property Identifier, Listing Rewards Contract, Rating Contract, Subscription Contract,
Spam Registry, Data Escrow Contract and 90 Cliff.
Rex’s Pilot will consist of a six-feature release:
1. Universal Property Identifier (UPI)
For every property listed in the RexIndexer, a unique property identifier will be generated. The
identifier will serve as that property’s genesis record for all future transactions. The UPI will be
2. Listing Rewards Contract
Pays x REX to every listing uploaded that is not voted as spam.
3. Rating Contract
Rex will deploy a trust system based on user ratings. Ratings will establish user-credibility
benchmarks that will be used throughout Rex’s ecosystem for listing validation, Registries and
4. Subscription Contract
Rex’s Subscription Contract will be deployed. To help with user onboarding through the
application layer, we’ve designed a non-crypto subscription model. Funds collected through the
subscription model will be used to automate transaction costs so the user does not have to to
obtain ETH in order to cover gas.
5. Rex Spam Registry
Rex will enact its default Spam Registry system.
6. Data Escrow Contract
The Data Escrow Contract will provide a trustless environment for users to exchange
7. Rex 90-day Cliff
Idle listings that have not been updated (via a transaction) for 90 days will be dropped from the
The current state of the Ethereum Network cannot handle significant increases in transaction
flows. Rex is working on various scaling solutions, to take features like listing edits off chain.
The team is exploring state/payment channels proposed by Raiden and following other
innovative solutions proposed by members like Matthew Di Ferrante.
4.4 Transactions: Escrow Contracts
One of the biggest transaction killers in real estate is time. Time delays often occur due to poor
communication channels and document distribution. Bank statements, estoppels and inspection
reports are just a few items that get passed around between the buyer, seller, landlord, lessee,
bank, insurance company, appraiser, tax assessor and inspector. These documents are often
passed through email and accurately tracking them is difficult. Rex solves this problem through
its Escrow Contracts.
First, all participants will visit the Transactions page on Rex’s application layer. Here,
participants will create a list of the necessary documentation that needs to be produced and by
which participant. Documents can include
Each user will upload their documentation which will be bundled into the Escrow Contract,
encrypted and pushed to IPFS. The contract will generate a private key, which the uploading
participant can share with other transaction participants that require access to the data. The
documents will only be accessible via the private key and for the duration chosen by the
Rex’s Escrow Contracts will have the ability to track deposits, payments, and allowances via the
Rex Token or cryptocurrency of the transaction participants choosing.
Rex will never store the documents or funds that travel through its Escrow Contracts. Instead,
the data and transaction records will be encrypted and sent via IPFS. The uploading participants
will have full control and ownership of the document, including when it can be destroyed and
who will have access to it.
Rex Technology Stack:
Data Escrow Contract
Listing Rewards Contract
4.5 Token Allocation
Founders and Angels will have a two year vesting period at no more than 1,000,000 REX a
year. This is to ensure price stability amongst the REX token.
4.6 Token Utility
Phases 1 and 2
1. Listing Rewards: Registered users are paid x REX for every listing they contribute to the
database that is not flagged and voted as spam.
2. REX Default Spam Feed: A user uploads a listing. It goes live on the platform and other users
have a one week duration period to mark it as spam. To mark a property as spam, the user
must pay x REX. The listing then goes into a three-day arbitration period where other REX
holders can vote (blindly) to approve or disapprove the listing as spam. If approved, the listee
gets the listing reward and the flagger loses their deposit. The loosing pool loses their REX and
it is distributed to the winning pool. If the listing is voted as spam, the flagger receives the listing
reward and pool that voted the listing as spam receives the losing pools REX.
3. Flagging Deposit: Users pay x REX to flag a listing they believe is spam. If the listing is voted
as spam by the community, the flagger will receive the listing reward. If the listing is not voted as
spam by the community, the flagger loses their deposit (see Rex’s Spam Registry).
4. Spam Voting Pools: Users pay x REX to vote for or against spam. All votes are blind and
tallied up at the end of the seven day voting period. The pool with 51% or more of the votes will
win the losing pools REX deposits. These deposits are distributed evenly amongst the winning
5. Listing Spam Reducer (LSR) Deposit: Users pay x REX when submitting a new listing. The
LSR is to prevent gaming of the Listing Rewards Contract. The listing reward will always be
higher than the LSR.
6. Curation Registry Application Fee: By default, users are subscribed to Rex's Spam Registry.
Rex’s Spam Registry is a screening process where spam listings are weeded out of the
application query. Other users can apply, be vetted and approved by other community
members, and create their own Curated Registries. The application fee is set in x REX.
Application Fees are redistributed back into the Listing Rewards Contract.
7 . Curator Approval Voting Deposit: Users can vote (blindly) on which users to
approve/disapprove for Curation Feeds. Voting to approve/disapprove user Applications to
Curate requires a REX deposit. For example, Bob lives in New York and believes he can filter
spam better than Rex’s Spam Registry. Bob applies, via Rex’s application layer, to become
Manhattan's spam curator for the downtown office market. Bob files his application and deposits
x REX into the Curation Smart Contract. Over a one week period, users vote blindly with REX
tokens to approve or disapprove Bobs application. If Bob is approved, the disapproving pool
loses their REX which are distributed evenly to participants in the approving pool. Users
subscribed to Bob’s Curation feed now see New York query results through Bob’s Curation
Feed. Bob can monetize his Curation Feed through advertising and listing promotions.
8. Curation Ad: Users that create Curation Feeds can monetize their Feed by charging REX for
promoting listings and advertising throughout their feed.
9. Market Sponsorships: Users pay x REX to sponsor a segment markets. These funds are
recycled back into the Listing Rewards Contract.
10. Featured Properties: Users pay x REX to Curators to feature their listings.
11. Broker & Landlord Professional Profiles: Users pay x REX to create a professional profile.
Users with Professional Profiles are searchable in the Rex Database. These funds are recycled
back into the Listing Rewards Contract.
4.7 Rex Node
REX Node’s are a combination of the RexIndexer, IPFS and Ethereum nodes.
Why Run a REX Node?
Today, users can visit a firm's website and browse "the firm’s" data. In fact, that data is not
being stored by the company at all, but rather a third party listing portal. This process
complicates the firm’s process for uploading listing data for several reasons:
Within the Rex ecosystem, firms can run a Rex node, store their information locally and own it.
The broker can upload listing information one time on the firm's branded website, which stores
the data on their Rex Node. This information can have daily pushes and pulls to nodes outside
their own. The firm can choose which data they want to participate to the global system, and
also have the ability to pull in outside information. Each firm that runs a REX node further
decentralizes the ecosystem ensuring the continuation of low fees and latency.
Benefits of running a REX Node
4.8 Listing Rewards
Listing Rewards provide a distributed means to build and scale the database. Anyone can
upload a listing to Rex. Each upload by the user will be eligible for the Listing Reward. Listings
that are not flagged/voted as spam will receive the Listing Reward.
4.9 Rex’s Default Spam Registry
Spam is a rampant problem all over the internet, and the eradication of such on the REX
platform is an important endeavor. Traditional real estate portals are filled with stale, fake and
misinformed data. In our research we've found most major review websites are able to weed out
approximately 70%-80% of spam through custom algorithms . However the last 20%-30%
must be curated by platform staff, which is costly and provides unbalanced incentive structures.
It becomes even more difficult as a platform scales outside its native geographic region.
Rex is taking a different approach. We believe real estate is a local business. With the
blockchain, we can employ new incentive structures that rewards users to localize spam
filtration, thus avoiding extensive hiring and unnecessary salaries. Rex is decentralizing spam
filtration using Registries and Game Theory.
Users that submit listings to Rex's application layer will be eligible to receive the Listing Reward.
The process will utilize a unique Curation system where other REX holders vote (blindly) on
whether to approve or disapprove a listing as spam. The process will look like the following:
The flagor’s "flag" will count as one vote to disapprove, and the listor’s vote will count as one
vote to approve.
In the case that listing x is approved as spam:
4.10 Voting Contract
Anytime a voting scheme is initiated, a 1:1 vote is automatically issued in the Voting Contract.
One to the flagger/challenger and one to the listee/curator. This creates a balanced starting
point for the voting process to commence.
4.11 User Curation Registries
Decentralization and the use of crypto-economics gives Rex the ability to take data aggregation
to new levels. Rex will employ User Curation Registries, which is a derivative of our Spam
Registry. This will further reduce spam and expand the available information thus leading to the
initial stages of the global real estate data marketplace.
How it works
Through Rex's application layer, users can apply to curate spam or create new types of data
feeds. The user will apply then be vetted by the community. If the candidate is approved, they
can begin curating data via their Curation Registry. If the user provides value to the network
they can monetize their registry via promotions and advertising.
Joe has been an office broker in New York City for 25 years. Joe regularly reviews Rex's office
listings and finds properties that make it through Rex's Spam Registry. Joe decides to file an
application to create Manhattan's Office Spam Registry. On his application, Joe lists his
experience and the ways in which he can add value to the network.
To submit his application, Joe deposits x REX. Joe’s application is routed to Rex’s Curation
Registry Applications Page. Over a one week period, Rex community members can vote to
approve or disapprove Joe. As in Rex’s Default Spam Registry, all votes are blind. To vote,
users pay x REX.
At the end of the one week period all votes are revealed and Joe is either approved or
disapproved by the community. If Joe is approved, the disapproving pool loses their REX which
will be distributed evenly to the approving pool. Joe’s deposit is routed to the Listing Rewards
Contract and Joe can begin curating office listings for New York City. Joe can monetize his feed
if he is able to accrue a following through listing promotions and advertising.
Users can challenge other user Curation Registries if they believe they are not doing an optimal
job. The application is similar to the application process of submitting a new User Curation
Registry, and will be voted on over a one week period, where like Joe's application, users will
vote blindly on whether to approve is disapprove the challenger.
If the challenger is approved by the community, Joe's user rating will decrease, and the
challenger will be granted the opportunity of replacing the previous Registrar. If the challenger is
able to reach the same amount of followers as Joe within "x" timeframe, they will be listed
number #1 position on the application layer for that market. Rex’s application layer will show up
to three Curation Registry’s per market and market segment.
Initially, there will be one curator per market, per segment:
4.13 Open Curation Reports
Users can aggregate and assemble new types of data, which can then be sold to other users
within the community. Each market will have a reports page where users can post data reports
to sell to other users. The listing seller will upload the data via Rex’s Reports Contract. The
reports contract will escrow the listing data via IPFS and the buyer’s payment.
4.14 Rex Subscription Contract
Rex will offer a subscription based model that will handle all backend transactions for paying
Rex believes people should be in control of their data. Users should have the ability to buy and
sell this data with other people in the industry. With today’s advances in storage, bandwidth,
distribution, and flexible blockchains like Ethereum, we can rebuild the old systems into cost
On Rex, users will retain ownership of their real estate data and it will not become a product of a
larger corporation. They will earn rewards and collect fees for their data, not the platform. New
marketplaces will emerge making it easier to obtain real estate data. A standard property
identification system will provide a secure way to transact property digitally. These goals can be
achieved with the technology and a proper strategy. The execution of this vision is malleable
and geared towards gaining the confidence of Rex’s users base and regulators around the
world. Modularizing development into achievable milestones provides Rex the ability to build,
test and deploy the platform so it can succeed and scale.
6.1 Stephen King
REX Founder Stephen King graduated from the University of Denver with a dual degree in
real estate and international business, going on to achieve a sterling career in real estate
finance, brokerage entitlements, and mixed-use property development. Prior to launching REX,
Stephen was Principal at King Interests, a full-service real estate firm based in Princeton, New
Jersey, and also led his own King Realty Group as President and Owner. Stephen has launched
several technology related startups in the real estate space in his career, and began
participating in the blockchain community in 2013, of which he is now organizer of the Princeton
6.2 Alex Jacoby
Alex Jacoby is our new Business Operations Director with a remarkably broad base of
experience in business processes and team development. Most recently, Alex led operations
and business analysis for VTS, a fast-growing, early-stage Commercial Real Estate tech
startup, enabling the team to grow from 13 to 95 employees and achieve three rounds of
funding. Alex established functional areas from accounting and finance, to HR and sales,
mapped the business architecture from end to end, and led its successful execution. During her
prior tenure at the largest nationwide distributor of balloons and related social expression
products—U.S. Balloon Co—the company was acquired by Party City. Alex led on all aspects of
B2B marketing, while launching the company’s Key Account Management team, and
streamlining Supply Chain Administration. Alex holds a BA in English Literature from SUNY
Albany, and a BA in Psychology from Adelphi University.
is a Software Engineer with a degree in Mathematics who specializes in full-stack
application development— JS, NodeJS, Python, Ruby, SQL, etc. He will be playing a major role
in the development of the REX platform. has worked as a remote-based technical lead
for a number of diverse, data-driven projects that help to bridge the gap between business ideas
and technology-based products.
6.4 Piyush Shrivastava
A self described “programming fanatic,” Piyush holds a Masters Degree in Computer Science,
and has been developing his skills in numerous coding languages since his youth. After
establishing himself as an elite web and mobile developer, he got the blockchain bug in 2013
and has shown himself to be a remarkably adroit and versatile hand at Solidity and NodeJS,
languages that provide the girding for REX ecosystem. Piyush is an avid puzzle solver, loves
Sudoku, and is a passionate gamer.
6.5 Ryan Song
Ryan began his involvement with REX as an active member of our community, fascinated by
blockchain technology and its potential to revolutionize countless industries. The REX vision for
the real estate industry has inspired him to join our team as Community Liaison, where he
functions as a first responder to inquiries and concerns. His willingness to help, paired with his
patience and sincerity, plays a key role in the growth of our community.
6.6 Edouard Barthelemy
Edouard is a Software Engineer with a Master of Engineering in Computer Science and Information Technology. Passionate about Science, Web, Systems & Networks, and Business, he spent the last 7 years putting is efforts in trying to design and develop useful applications in order to enhance people lives. His experience includes Research & Development in the Online Game, Telecommunication, Telephony & Call Center, and Real-Time IT Support industries solving complex issues using the best of cutting-edge technologies: Ruby, Node.js & React.
Rex Landing Page http://www.rexmls.com
Rex Blog http://www.rexmls.com/blog.html
8. To Catch a Fake: Curbing Deceptive Yelp Ratings and Venues
Mahmudur Rahman1 , Bogdan Carbunar1∗ , Jaime Ballesteros2 , and Duen Horng
The School of Computing and Information Sciences, Florida International University, Miami, FL
Nokia Inc. Chicago, IL, USA
School of Computational Science & Engineering, Georgia Tech, Atlanta, GA, USA
Received 13 May 2014; revised 13 November 2014; accepted 3 March 2015
Published online 10 April 2015 in Wiley Online Library (wileyonlinelibrary.com).
8.1 Appendix A Real estate transactions: Today
A buyer, tenant or broker searching for a house, office, warehouse, land or retail space typically
begins their search with an online portal. The accessible data is limited before the user hits a
paywall. The paywalls consist of annual memberships that enlist high annual fees and collect
superfluous data about their customers and their dealings.
After the user subscribes and locates a property, they engage the listing agent to negotiate
price. The buyer and seller have their attorneys draft, edit, and finalize the Purchase & Sale
Agreement (PSA). Within the PSA are a list of terms the buyer and seller must perform for the
transaction to consummate. The buyer is permitted approximately 30-90 days to perform an
analysis of the property called due diligence. Due diligence includes, but is not limited to:
The buyer’s lender will conduct:
During due diligence, the seller will perform certain obligations spelled out in the PSA:
Throughout the transaction, the buyer and seller communicate through their banks, attorneys,
inspectors and real estate brokers. The chain of communication inevitably leads to delays and
increased costs to the buyer and seller.
Once diligence expires and both sides meet their respective obligations, a closing date is set.
The following is a brief list of documents required at closing:
In the US, closing costs average approximately +$10,000 for residential and approximately
+$20,000 for commercial (subject to the size of the deal and local tax jurisdictions).
Bob wants to sell a mixed use building in Princeton, New Jersey:
Address: 236 Nassau Street
9 1-bedroom apartments
2 retail units
Net Operating Income: $175,000
Capitalization Rate: 5%
Bob decides to list 236 Nassau Street on his local portal service. After several weeks and no
traction, Bob decides to sign up for the portals premium edition (approximately $299.95/month).
The premium edition grants Bob access to surrounding property data. After three weeks and no
action, Bob decides to obtain a comparable property analysis. Bob pays approximately $90.00
for the service. The information is dated and proves useless. Bob realizes 236 Nassau is at the
bottom of the search query. For an additional fee of approximately $399.95 for 30 days, Bob can
have 236 Nassau Street listed as "Platinum" on the results page. Bob proceeds with the
Bob is spending approximately $790.00/month or $790.00/per listing on marketing 234 Nassau
Alice’s broker finds Bobs listing on the portal and presents it to Alice. Alice makes an offer of
$3,400,000. Bob accepts Alice’s offer and their attorneys negotiate the Purchase & Sale
agreement on the following terms:
Alice deposits $175,000 in her attorney’s escrow account. Due to miscommunication between
the title agency and bank, closing is delayed two weeks costing both Bob and Alice money in
attorney fees and carrying costs. Finally, a closing date is set, and after several hours of
paperwork, title is passed. Title is recorded manually at Princeton’s municipal clerk’s office.
Alice and Bob paid approximately $40,000 in combined transaction costs and Bob paid
approximately $790.00/month in listing fees.
8.2 Appendix B Lease Transaction
Alice, a broker for CBRO, lists a 25,000/SF office suite on REX. Bob, a broker for Ether Realty,
shows 123 Alpha to his client, Osprey Inc. Osprey proceeds with a 10-year lease with the
Property: 123 Alpha Street, Sydney Australia
Tenant: Osprey Inc.
Term: 10 years
Lease Contingencies Osprey Inc. (Tenant)
123 Alpha Street, Inc. (Landlord)
123 Alpha & Osprey’s council collaborate to sign the above into a smart contract on Rex. The
contract can be amended anytime by having both parties broadcast a transaction to the
contract. The contract and changes are viewable in real time on the blockchain. 123 Alpha Inc.
and Osprey Inc. agree to use a stablecoin to handle the transfer of funds. All money is
escrowed and released according to the terms in the smart contract.
123 Alpha Inc. and Osprey Inc. benefit from a transparent smart contract where changes are
viewed and agreed upon quickly. Efficient communication channels lead to a decrease in time
and fees. The transaction is permanently recorded on the blockchain providing a secure means
for record keeping and lease renewals. CBRO and Ether Realty are paid on time according to
the smart contract negating the need for invoicing and payment follow ups; completing our
8.3 Appendix C Tokenized Ownership
What if you could trade 1,000 tokens in the Chrysler building like you trade a 1,000 shares of
The Chrysler building was completed May 27, 1930. Owned by Walter P. Chrysler, it was built to
serve as Chrysler's new headquarters. The Chrysler building is 77 floors high and approximately
2,062,772 square feet in office space. The building has changed hands several times since the
Chrysler family sold it in 1953. In 1998, Tishman Speyer Properties along with Travelers
Insurance purchased the Chrysler building for $220,000,000. In 2001, Tishman sold a 75%
stake to Abu Dhabi Investment Council. Today, Abu Dhabi Investment Council owns 90% and
Tishman retains 10%.
Redefining Real Estate Ownership: Chrysler Dapp
Let’s say Rex purchases Abu Dhabi’s and Tishman’s entire stake in the Chrysler building for
$3,000,000,000 cash at a 4% capitalization rate:
The Chrysler building is 90% occupied with long term leases averaging $108/SF. The gross
income is $200,500,000 per year. Expenses run about 40% or $80,200,500. Thus, the Net
Operating Income is $120,000,000.
Blockchain Using Ethereum, Rex creates a decentralized application called Chrysler Dapp. The
Chrysler Dapp creates 1,000,000,000 CHRY tokens. Chrysler Dapp allocates 750,000,000
CHRY tokens (75% of the total supply) to be sold in an upcoming crowdsale. CHRY tokens will
be listed at $3.00 per token (valuing the building at $3,000,000,000).
The developers of Chrysler Dapp create an incorporated company called Chrysler Management
Inc. Chrysler Management Inc. will be the managing entity of the Chrysler building, responsible
for management, leasing and legal. Chrysler Management Inc. will retain 100,000,000 CHRY or
10% of the total supply. The remaining 150,000,000 CHRY will be held for capital reserves.
Each quarter, Chrysler Management Inc. will convert all positive cash flow (after expenses) to
CHRY tokens and deposit them in a community smart contract. The contract will distribute
CHRY tokens to stakeholders according the percentage of tokens each stakeholder owns.
In the bylaws between CHRY token holders and Chrysler Management Inc., it will state that
each quarter (much like public companies are required by the SEC), Chrysler Management Inc.
is obligated to release a detailed income and expense report for that quarter.
Token participants have the opportunity to own a piece of an iconic building in New York City
with a potential 10% upside: If Chrysler Management Inc. leases the 10% vacancy, it will
increase net operating income which in turn should increase the value of the building:
> vacancy + tenant = +NOI = +building value = +CHRY token value
Market equilibrium shows us an increase in value usually creates an increase in price.
Conversely, if Chrysler loses a major tenant the token’s value should decrease.
As we’ve seen with recent token sales, prices fluctuate and markets can be highly irrational.
However, a physical asset like the Chrysler building can be pegged to the local real estate
market offering a more precise determination of value and perceived risk.
ABC Inc. occupies 500,000/SF at $108/SF. Their lease expires and they vacate the Chrysler
building. In one deal, the asset loses $54,000,000 in gross annual income. The CHRY token
price drops to $1.00 valuing the building at $1,000,000,000. A few sophisticated individuals
discover the actual market value (after the loss of ABC Inc.) should be closer to $1,700,000,000:
$146,500,000 — $80,200,000 = $66,300,000 NOI at a 4% CAP = $1.657 billion or $1.67 per
The investors can profit from a potential $0.67 upside in token value, long term building
appreciation and any increase in value once the remaining 10% vacancy is filled.
The same is true if the token value jumps to $4.00 or $4,000,000,000 with no real increase in
NOI. Sophisticated investors may short CHRY tokens thus stabilizing value with market