
Microsoft Office Excel
DealForge
DealProfit
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Google Sheets
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.

JavaScript.com
JavaScript Quiz
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dateDropper Javascript
A full list of JavaScript operators with examples
Which is more popular?
Based on our record, JavaScript Operator Lookup seems to be more popular. It has been mentioned 1 time since March 2021.
Website, pricing, platforms and company facts side by side.
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| Website | keptdo.com | joshwcomeau.com |
| Pricing | — | |
| Company | Startup from the United States · 1 - 9 employees · 2026 | — |
| Listed in |
In their own words, as submitted to SaaSHub.


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...
No description of JavaScript Operator Lookup yet.
What each product offers, as listed by its team.


Possible disadvantages
An editorial look at what each product does well and who it suits.


Overall verdict
Why this product is good
Recommended for
No analysis of JavaScript Operator Lookup yet.
How often each product is chosen within a category, 0–100% relative to the other.


As answered by people managing KeptDo and JavaScript Operator Lookup.
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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Recommendations tracked on public social media and blogs since March 2021.


Tracking KeptDo since Jun 2026.
If you replace your || with ?? You should get the behaviour you are after. This is a good reference for what the operators do in js: https://joshwcomeau.com/operator-lookup. Source: about 5 years ago
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