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Propty.uk
The AI deal-analysis platform that turns a 40-hour multifamily deal analysis into a 2-hour one built by an operator, for operators. The Multifamily Deal Analyzer Pro gives active syndicators, operators, and investors a complete all in one solution.

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Based on our record, CodeSandbox seems to be more popular. It has been mentioned 313 times since March 2021.
Website, pricing, platforms and company facts side by side.
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| Website | codesandbox.io | keptdo.com |
| Pricing | ||
| Company | Startup from The Netherlands · 1 - 9 employees · 2017 | Startup from the United States · 1 - 9 employees · 2026 |
| Listed in |
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No description of CodeSandbox yet.
The AI deal-analysis platform that turns a 40-hour multifamily deal analysis into a 2-hour one — built by an operator, for operators. The Multifamily Deal Analyzer Pro gives active syndicators, operators, and investors a complete underwriting and deal-analysis framework to make decisions. Model...
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As answered by people managing CodeSandbox and KeptDo.
KeptDo's answer:
Commercial Multifamily Operators and Investors
KeptDo's answer:
Supabase, Vercel, Python, Claude Code,
KeptDo's answer:
As a multifamily operator with 246 units and a 25-year IT career I build this on functionality to address everything you will need to make a decision on a deal.
KeptDo's answer:
All in one solution, continues development and improvement, build for operators by operators
KeptDo's answer:
I've worked in IT my whole career — from systems engineer to Director, most recently as an IT Manager. Twenty-five years of building systems, leading teams, and solving the kind of problems where you can't hand-wave the details.
In 2024 I really got into AI. Not the demo-day AI — the kind that solves real business problems. And around the same time I shifted my own focus from residential real estate to commercial multifamily, where I was struggling to analyze deals as quickly and thoroughly as I wanted.
Two converging things: I was learning what AI could actually do, and I was personally bottlenecked by the same workflow every active syndicator has. So I decided to do something about it.
The workflow that breaks everyone It's not one moment. It's a thousand small ones.
A broker drops a packet in your inbox. You hope it's in a format your model can read. It isn't. So you spend 30 minutes to 4 hours formatting it, depending on how rough the package is. Then you copy values into your model. Then you match T-12 figures. Then you align the rent roll. Then — finally — you have a basic analysis you can work with.
But you're not done. Now you need market analysis. Sensitivity. A real defensible buy decision. That's another half day. Sometimes a full one.
The PDF-to-Excel grind is what did it for me. Rent rolls coming in with every layout under the sun, and me manually aligning them so my Excel model could read them. That's when I said: enough of this.
3 AM is not a strategy I'm the type of person that won't stop. That's just how I'm built. So I was constantly up until 3 or 4 in the morning underwriting deals. I had to, to compete.
But then I asked myself the real question: what if I took that same energy and worked smarter on something that would dramatically cut the late nights? And what if I could help other operators do the same?
That's how the concept came about.
Why existing tools didn't solve it CoStar is a great tool. It's genuinely amazing. It's also ridiculously expensive, and it doesn't do what I needed it to do — like show the investor what their journey looks like over the hold.
Excel templates? You've seen the math above. They're flexible and they're mine, but they cost me hours per deal.
There was nothing on the market that did what I needed in one product at a price an active syndicator running $5M–$200M could actually justify.
So I built it.
KeptDo's answer:
Level 7 Investors Level 7 Capital Management ThomasLynne Properties
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Codesandbox is an online code editor and prototyping tool that makes creating and sharing web apps faster. Codesandbox: Online code editor and ide for rapid web development.
CodeSandbox can be thought of as a much more powerful and complete take on JSFiddle. True to its name, CodeSandbox provides a complete code editor experience and a sandboxed environment for front-end development.
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To begin, you can start creating your own react app using the command line or can directly go to CodeSandbox if you want to skip using the command line which is faster. CodeSandbox is an online code editor and prototype tool that speeds... - Source: dev.to / 5 months ago
To begin, you can create a react app using the command line or any code editor (e.g., VSCode). You can also try using CodeSandbox as an online code editor that is simple to use and allows you to deploy your code. - Source: dev.to / 5 months ago
If you are in a rush to open unknown repos, use GitHub Codespaces or codesandbox with Copilot or another AI integration to analyze the repo for malicious intent and to run it in a safe environment. - Source: dev.to / 11 months ago
Tracking KeptDo since Jun 2026.
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