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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?

Monthly rent ÷ price%
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 outside your band, 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 case, where cash-on-cash stops applying because nothing is left in the deal.

Hard money & HELOC carrying costsHolding costs: property tax · insurance · utilities · maintenanceCash 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.

Saved to your account, on every browser

Every deal is saved to your account: encrypted in transit and at rest, isolated to you. Sign in from any browser and your portfolio is already there. No spreadsheets to email yourself.

Instant, on-device analysis

The calc engine runs in your browser, 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

Send a listing from a supported listing site to a pre-filled Quick Analysis, no retyping. 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.

Inside the app

What a finished analysis looks like.

These are screens from BuyBox's results page for a real listing, run with the default assumptions. The verdict is whatever the engine reached: this deal came out High Risk, with four metrics flagged. The trial runs the same analysis on your own listing.

BuyBox results page for 1434 Lillius St, Abilene, TX: a High Risk verdict with a BuyBox score of 28 out of 100, and the four headline numbers: cash flow $165 a month, unlevered yield 7.9%, cash on cash 4.9%, cash invested $40,445.
The verdict first. A 0 to 100 score, how many metrics are strong, workable or concerning, and the four numbers you'll act on.
Survival, returns and equity metrics for the same deal, each with its target and a strong, workable or below grade, plus the capital stack.
Every metric against its target. Survival, returns and equity, each graded against your buy box.
Four risk flags for the same deal: cash flow per door, percent of ARV, cash on cash and IRR, each with the value and a one-line reason.
What's wrong with the deal, in plain words. Flags name the metric, the value and why it matters.

Sample deal. Real listing, run as a sample. Not investment advice.

Run your next listing through it.

Start free in your browser, no download, no card.