How I Use Claude to Find Cash Flow Positive Rentals

What you'll build

A system for underwriting rental listings with plain Claude in the browser - no Claude Code, no scraping, no APIs. You feed it full-page screenshots of Realtor.com listings, and it runs identical cash-flow analysis on every property, filters out the ones that don't pencil, and hands back a printed-ready PDF: a one-page summary per property, an optimized tour route, a tour-day prep checklist, and questions to ask every listing agent.

I built this when my dad decided to look at rental property in New Britain, CT - an hour-and-a-half drive away - with a realtor family friend. I started with 40+ listings from my saved searches and walked into every showing already knowing the numbers. Even the realtor, 30-40 years in the game, works off the dome and a 2-minute Zillow skim; this gets you the in-depth research off the rip.

This is the follow-up to my deal-hunting video (the saved-search + scheduled-task setup): https://www.youtube.com/watch?v=MtlE14HC9G0

What you'll need

• Claude (the regular browser/chat version)
• Chrome (for DevTools)
• Realtor.com saved searches set up for your target area
• A printer, if you actually go on the tour

Step 1: Run your saved searches on Realtor.com

Open Realtor.com and run the saved searches for your area. Open each results page (or listing) in its own tab. Mine surfaced 40+ properties across the individual searches.

Step 2: Capture each page as one full-size screenshot

Realtor.com has no Claude integration and blocks scraper/Playwright-style automation. Don't fight it - bypass it. Claude reads the pixels instead.

On each tab:

Right-click → Inspect   (or Cmd+Option+I)
Cmd+Shift+P
Type: "full size screenshot" → Capture full size screenshot

Chrome saves one tall image of the entire page - every detail, no stitching multiple screenshots together.

Step 3: Paste the screenshots into Claude with the cash flow prompt

Dump the screenshots into Claude. My prompt was nothing complicated - close to this, verbatim from the video:

I'm sending a bunch of screenshots of properties in New Britain. You're going
to run an analysis on them in terms of cash flow - whether they're cash flow
positive, number of beds and baths, the cap rate. The ones that don't make
sense, disregard. The ones that do make sense, aggregate them all - I'm going
to book tour dates for them. We're okay with a 20% down payment.

Claude will come back with questions about how to format the response - answer them. (I could make this prompt 10x better just by asking Claude to improve it, but simple worked.)

The consistency is the point: a human analyzing property #16 is not as sharp as they were on property #1. Claude runs the identical analysis at the same level on every single one.

Step 4: Let it filter and aggregate

Out of the 40+, Claude kept 11 strong (or relatively strong) candidates and disregarded the rest. The output became a ~12-page PDF, one page per property:

• Property details and acquisition numbers
• Monthly cash flow (the number that matters most) and cap rate
• Details pulled from the listing description a skim would miss - e.g. flagging that on a 1915 build, the boiler and hot water heater have likely been there a long time, so ask the listing agent about them

Step 5: Build the tour route and itinerary

Since I was driving 90 minutes, I had Claude aggregate all the shortlisted addresses and map the most efficient route. It also produced a tour itinerary: top priorities, which agent to contact for each property, their numbers.

Step 6: Print it and carry it

I printed the whole packet and had it in hand at every showing. On the drive up I read each property's page, so when a listing agent raised something, I already knew it. The parts that earned their keep:

• Tour day prep checklist - take pictures of the electrical panel, boiler, furnace. I wouldn't have known to do that.
• Red flags per property
• Questions for every listing agent - plus scripts for calling them, which mattered as a first-timer at investment properties

That's it. None of this replaces a pro - but it means you're not walking in blind. And it cuts both ways: a real estate agent could run this standing search for a client and send them polished reports automatically, and a buyer can do their own due diligence before ever getting in the car.

Resources

• Realtor.com - https://www.realtor.com (saved searches; setup in the previous video)
• Previous video - the automated deal scanner: https://www.youtube.com/watch?v=MtlE14HC9G0
• Wispr Flow - the voice-to-text I use to talk to Claude, 1 month free: https://wisprflow.ai/r?AUSTIN16480