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Features

The whole underwrite, on one machine.

No tabs of broken spreadsheet formulas. BuyBox computes every number a buy-and-hold or BRRRR investor needs (the industry-standard way), and scores it against the criteria you set.

Survival

Will it keep the lights on every month?

Rent-to-price ratio%
DSCR×
Break-even occupancy%
Cash flow per door$
Operating expense ratio%

Equity

How much cushion is built in on day one?

All-in cost ÷ ARV%
Equity cushion$ / %
Rehab estimate (tiered)$
Regional cost multiplier×
Unlevered yield on cost%

Returns

What does the money actually earn?

Cash-on-cash return%
Internal rate of return%
Cap rate%
Gross yield%
Net operating income$

Every figure ships with a threshold chip, strong, workable, or below, set by your buy box.

BRRRR engine

Refinance math that matches the closing statement.

Model the bridge financing, the rehab hold and the DSCR cash-out refinance end to end. BuyBox computes the net proceeds you actually pocket (not loan-minus-basis hand-waving), so you know precisely how much capital comes back out, including the fully cashed-out "infinite return" case.

Hard money & HELOC carrying costsHolding costs: tax · insurance · utilitiesCash left in deal
DSCR cash-out refinanceEST
ARV$232,000
New loan @ 75% LTV$174,000
Refi closing (3%)−$5,220
Payoff existing−$142,500
Cash back at refi$26,280
Cash left in deal$3,200almost out
30-year projection
YrCash flowEquityCum. CF
1$3,828$54,300$3,828
5$5,012$92,140$21,930
10$6,740$148,600$51,180
20$10,910$268,400$137,500
30$17,640$432,900$281,300
Projections

See the next 30 years before you sign.

Project rent growth, appreciation, expense creep and loan paydown year by year. Run a hypothetical sale at any exit and get total return, AAR and CAGR, plus a full month-by-month amortization schedule.

Computed on your device, saved to your account

Every deal is computed on your own machine and saved to your account: encrypted in transit and at rest, isolated to you. Sign in on any device, web or desktop, and your portfolio is already there. No spreadsheets to email yourself.

Instant, on-device analysis

The calc engine runs on your own device, not on our servers, so analysis is instant and keeps responding even if our services are briefly unavailable. You’ll need to be signed in, and saving needs a connection.

Chrome capture extension

Grab a Zillow, Realtor.com or Redfin listing in one click and send it to a pre-filled Quick Analysis. Beds, baths, sqft, price and photos extracted automatically.

Rentometer rent comps

Connect your Rentometer API key to auto-estimate market rent on address entry, or type your own number any time.

Portfolio tracking

Close a deal and it moves to your portfolio (rehabbing, stabilized, listed or sold) with actual-vs-projected performance and a final IRR at disposition.

Source-tagged inputs

Every value is tagged EST, ASM or ACT so you always know what's a guess and what's real.

Proof

Read a real report before you sign up for anything.

A complete BuyBox export for 1420 Sample Street, Columbus, OH (sample deal): every metric, the assumptions behind it, and the verdict the engine reached, including each metric it flagged. We publish whatever verdict the engine gives this deal, good or bad, rather than a deal picked to flatter the product. Open the report, or download the spreadsheet and change an input to watch its formulas recalculate. No account, no email.

Sample analysis. Illustrative deal, not investment advice.

Run your next listing through it.

Start free in your browser, no download, no card. Optional Windows desktop app included.