About Comps Calculator

Comps Calculator is an independently built tool for evaluating real estate deals — rental properties, house flips, and BRRRR investments — without building a spreadsheet from scratch every time a new property comes up. It was built to answer one question quickly: does this specific deal, with these specific numbers, actually work?

Why this exists

Most investors evaluate deals the same way at first: a spreadsheet with rows for purchase price, rehab budget, rent, financing terms, and a handful of formulas copied from a forum post or a course. That works, but it's slow to iterate on and easy to get wrong — a stale formula, a copy-paste error, or a forgotten expense line can quietly throw off an entire analysis. Comps Calculator keeps the same inputs a spreadsheet would use, but runs the math consistently every time, across three of the most common investment strategies.

What it actually calculates

Every number on the site is derived from the inputs you enter — there's no external data feed and no hidden assumptions beyond what's shown on the page:

• Buy & Hold (Rental): monthly cash flow, Cash-on-Cash ROI, Cap Rate, and Net Operating Income from purchase price, financing terms, rent, and operating expenses.
• Fix & Flip: total project cost, hard money financing costs, holding costs, selling costs, and net profit, checked against the 70% Rule.
• BRRRR: the full Buy, Rehab, Rent, Refinance, Repeat cycle — cash left in the deal after refinancing, equity created, and post-refinance cash flow.

The full breakdown of each formula is available on the calculator itself.

What it isn't

Comps Calculator isn't a brokerage, a lender, or a source of property data — it doesn't pull comps from an MLS or estimate a property's value for you. You bring the numbers (from your own research, an agent, or a listing), and it runs the analysis. It's also not financial, legal, or tax advice — see the disclaimer for details on that.

Questions or feedback

If something looks wrong, or there's a feature that would make this more useful, the contact page goes straight to a real inbox.