Building A Better Feasibility Ecosystem: The Real Estate Execution (REX) Model

We’d like to announce a new way we’re shaping feasibility studies in the built environment. Let’s take a look at where TestFit is now and look into the future of a better feasibility ecosystem—the Real Estate Execution (REX) Model.

TestFit in 2022

My co-founder Ryan Griege and I started with two customers in October 2017. Now TestFit Inc. has grown into a fully-fledged corporation with multiple teams and a beating heart of its own. After over 40 product updates and 20 hires, our customers now include hundreds of firms across the world.

Most are architects and developers, working diligently to solve or kill real estate deals with TestFit’s building configurator. Alongside this core feasibility work, we have seen 3 key trends (outside of our architectural innovation) that will shape the next arc of TestFit’s journey:

1. QTO & Proforma

Our development customers requested connectivity from the TestFit configurator to their pro-forma software, to understand the financial analysis of the proposed design. They had also cited a need to have high fidelity designs with pricing, needing an edge on information to win competitive sites and kill bad ones.

2. Time-Based Delivery

Another trend has been construction-driven firms. We have been serving general contractors that build from a constrained kit-of-parts, or productized mindset. They do this to deliver same-quality buildings more quickly, or cheaply, or both. In nearly every case, these teams deliver buildings faster than their competitors.

3. Faster Architectural Information

Real Estate Developers are creating and executing entitlement packages using TestFit data on slews of sites. Information that is both richer than traditional methods, and delivered in a fraction of the time.

In all of these above cases, we provide crucial architectural information instantly. Whereas before, it would take weeks to receive or simply be inaccessible.

Improve Housing Supply with Outcome-Based Modeling

If design teams and construction teams can optimize for any given KPI together, like the project level IRR, opportunities for improved housing supply execution will be available.

By making housing and commodity building types more competitive to build, it will result in more buildings that humans need. 

We believe that outcome-based modeling software can unlock:

  • Instantaneous constructability analysis for preconstruction
  • Deep integration with financial proformas
  • Federated access to curated pricing and sourcing information

All of these workflows, in essence, are illuminating risk-adjusted construction and development data the moment the architectural information is available. How we enable precon and pre-development teams to de-risk their information will be another core arc for TestFit Inc. To do this, we will work around a very simple framework: the Real Estate Execution model.

The Real Estate Execution (REX) Model

The REX model is a software system focused on cost, constructability, and design. The basic goal of REX is to meaningfully combine proforma, pricing, and building design into one model, so deal teams can work more effectively. Delivering coordinated documents with millions of model elements can wait until after the big decisions are fleshed out.

TestFit Real Estate Execution Model

Real estate feasibility has grown to consume vast amounts of corporate resources. Regulations are up, funding sources are difficult to identify, pricing has vast volatility, and managing all of this information is getting in the way of real estate development happening. 

Buildings delivered with a highly productized approach—typically with heavy prefabricated or modular construction—are great examples of the REX model driving the delivery fundamentals. These systems are essentially tiny real estate execution models on their own: self-contained pricing, design, and delivery. 

The REX model will enable real estate deal teams: the architects, developers and general contractors, to collaborate instantly on real estate deals, with the software stack focusing on what questions matter at the outset. Deal teams can collaborate on entire pipelines of projects, codifying joint approaches to solving deals.

Outcomes of Utilizing REX

Every big idea has some very meaningful practical benefits. REX is not immune to this:

  • Lowering the friction for deals to be assessed means that more deals will be considered, with higher quality analysis.
  • True lifecycle analysis, lowering the friction for DfMA to be used in every deal
  • Improved purchasing power for DfMA suppliers
  • Improved access to productized markets
  • Data to influence change in policies and zoning based on informed economic models
  • Frictionless, team-based site selection
  • Acceleration of good real estate deals into schematic design or design development

It Takes an Ecosystem

To bridge design tech, contech, and proptech with the most comprehensive feasibility tool possible, we are endeavoring to build “Real Estate Execution Modeling”. TestFit will be working with our customers, other companies, and industry stakeholders to refine REX so users can deliver better outcomes. We believe that by integrating pro-forma, costing, and design, the REX model will lead to significant productivity improvements within the commodity industry, changing how the real estate industry collaborates on the loss-leading part of every AEC firm. 

We’d like to announce the closing of our Series A, led by Parkway Venture Capital to fulfill our vision of REX for our customers.

How to fast-track feasibility phase collaboration with TestFit

In a perfect world, collaboration during the feasibility phase of site development would be easy. 

But in the real world, the developer, architect, and contractors often don’t have enough time or financial incentive to work deeply together. A critical factor is that the tools available in the market don’t allow them to move fast enough. 

🛑 The developer doesn’t have the luxury of weeks to make decisions on a new property – they need to know if this deal pencils or not quickly.

🛑 The architect needs to convert the Pro Forma into a viable spatial design that meets the site, and existing tools are highly manual.

🛑 The contractor doesn’t want to invest heavily in something that might not actually happen. But if this project does move ahead, they need to advise on cost and constructability rapidly.

In order to develop the right site plan quickly that will win that deal, you need the combined expertise of all three stakeholders. 

TestFit creates a space for stakeholders to come together to integrate those different pieces of knowledge. With all that expertise at the table, you’re able to iterate rapidly, make the most of every development dollar, and de-risk the development process.

Keep reading for a collaboration workflow with TestFit, plus some real-life examples of what successful collaboration looks like.

Fast-track your collaboration workflow with TestFit

A collaboration workflow with TestFit centers on the idea of Real Time Deal Prototyping (RTDP). Typically, this can be done from start to finish in under 1 hour.

Fig 1.0 – A feasibility phase collaboration workflow with TestFit.

1. Set up TestFit file with known constraints

First, the developer needs to set up a TestFit file with known deal and site constraints, such as land area, setbacks, zoning parameters, unit types, parking ratios, etc. You can check out our How to Use TestFit YouTube series to learn how.

Fig 2.0 – Mapping out site plans in TestFit.

TestFit’s Kit of Parts (KOP) allows the developer to constrain the test fitting process to their standard units. 

Fig 3.0 – Defining a TestFit Kit of Parts for using configurator 

With the constraints of the site, and the desired unit sizes, the team can now rapidly explore the potential approaches to development. 

2. Iterate live with stakeholders

This is where the magic happens! After the developer has input those site and deal constraints, the architect and contractor can join the fun.

Rather than a typical feasibility study workflow where design options can take up to 8 hours per solution, TestFit allows architects to generate and iterate through options in under 30 minutes.

Fig 4.0 – Rapid iterations exploring design options in TestFit by The Geyser Group.

From here, the contractor can give high-level feedback on the constructability of the proposed development approaches. They should also be able to improve hard cost assumptions with cost information that’s relevant to buildings in that area. 

One of the biggest benefits of collaborating in TestFit is that deal iterations happen in real time, so teams can instantly understand the tradeoffs between building program, cost, and building form. 

For example, with each new iteration:

  • The developer can see the yield on cost 💵
  • The architect can look at the spatial design in 3D 🏨
  • The contractor can track key quantity metrics 🏗️

Fig 5.0 – TestFit’s Development Panel tracks financials in real-time.

3. Agree on a layout and yield on cost estimate

After a round of rapid-fire iterations integrating the expertise of the developer, architect, and contractor, it’s time to commit to a winning site plan and fine-tune the deal.


The Tabulation tab on TestFit’s output panel provides key metrics for the contractor to estimate the cost of the deal. Expanding the tabulation will show instant takeoff calculations done by Test Fit.

Fig 6.0 – Track key quantities and takeoffs in TestFit’s tabulation tab.

The Deals Editor allows the developer to evaluate the costs and revenue from the TestFit. They can also add key data from the Pro Forma, such as assumed costs, targeted rents, or proposed land value, without giving too much information away.

Figure 7.0 – Evaluating costs and revenue in TestFit’s Deals Editor.

This is the sort of radical collaboration the TestFit enables –  everyone has access to the information they need to do their job, and can integrate their knowledge for effective collaboration. 

Ultimately, this leads to faster test fits, better investment decisions, and happier occupants.

Real-life examples of successful collaboration in the feasibility phase

We’ve covered the theory, but maybe you’re still wondering what happens when the rubber hits the road? Keep reading for real-life examples of successful collaboration on both multifamily and industrial deals.

Example 1. A large multifamily deal

Novin Development Corp., an affordable housing developer in Walnut Creek, CA, used TestFit to fast-track collaboration during the extremely competitive process of securing affordable housing subsidies. 

Faced with more than 30 prospective sites, the team used TestFit to move quickly through a collaborative decision-making process that led to a successful acquisition on an ideally suited site.

Figure 8.0 – An initial TestFit made by Novin Development Corp. for an affordable senior housing development.

After outlining initial estimates with TestFit takeoffs, Novin Development Corp. brought on an architect and contractor to validate pricing and give a more detailed estimate. This initial TestFit gave the architect a much more informed starting point to guide their initial design work, which really sped up their process. 

As soon as the site was under contract, the architect went straight into design work allowing the developer to demonstrate project readiness and compete for state funding ahead much faster.

Figure 9.0 – Rendering of 603 A Street in Hayward developed from the initial TestFit.

The team successfully secured $7.4m in State TOD funding, going from site plan to funding in just 2 months instead of the usual 6-8 months.  

You can read the full case study with Novin Development Corp to see their process in more detail.

Example 2. An industrial development deal

Industrial deals present a very different challenge to multifamily deals. Instead of looking at a building’s performance contextually on a site, you’re looking at how to solve a much larger logistics problem in how the building fits into a supply chain.

Figure 10.0 – Creating a site plan with TestFit Industrial.

TestFit Industrial can help with taking parcels of land and arriving quickly to a yes/no as to whether a viable facility can work on the site.

Seeing the trade-offs between layout and operating costs in TestFit in real-time brings immediate clarity to the architecture, developer, and construction teams.

Build an industrial site in seconds

Figure 11.0 – Test fitting an industrial site plan in real-time.  

With TestFit, the starting point for discussion between stakeholders happens in days, not weeks, allowing the developer to get to that site plan quicker. 

TestFit speeds up a very cumbersome process. [TestFit Industrial] helps to remove risk for developers during the site evaluation process. I believe TestFit is on its way to becoming the standard bearer for go/no-go decisions regarding the early financial wherewithal of a development deal.

Mike Jones, Executive, Pankow Builders

Benefits of feasibility phase collaboration you can’t afford to miss

With so much at stake at the feasibility stage, fast and effective collaboration is vital. Any time wasted on a no-go site is an opportunity cost for all stakeholders. 

Here are some of the key benefits of feasibility phase collaboration you can’t afford to miss out on: 

👍 Developers de-risk their development decisions by bringing in the expertise of their architect and contractor earlier.

👍 Architects are able to deliver better design services faster. That competitive edge means everything when pursuing new work.

👍 Contractors can find a simpler path to an estimate with a better understanding of the tradeoffs between the Pro Forma, design, and costs.

Better collaboration in feasibility really is possible! If you’re ready to start TestFitting, you can book a demo with a TestFit specialist or try TestFit out for yourself.