RentalUnderwriter
Built for 2026 rates — honest defaults, not guru math

Know if the deal works
in 10 minutes.

A professional-grade Excel toolkit that takes a listing and tells you, in plain English, whether it cash flows, what it's actually worth to you, and what will break it. Every formula visible. Nothing locked.

Start free: run a deal through the calculator →

Or download the free rental analysis spreadsheet (.xlsx) and the 48-point due-diligence checklist — no email required.

$19$49LAUNCH PRICE
Secure checkout by Stripe · Instant download the moment you return · Refund on request, no questions

Most first rentals fail for one reason

The buyer trusted the listing's numbers. "Pro forma" rent, no vacancy, no CapEx, no property-tax reassessment. The spreadsheet said $312/month of cash flow; reality said minus $190.

This toolkit exists to make that impossible. It pre-loads the reserves lenders and experienced operators actually use — vacancy, maintenance, CapEx, management — so a deal has to survive real assumptions before it looks good.

See it work

Yellow cells are yours to type in. Green cells calculate. Verdicts are plain English.

Purchase price$245,000
Down payment 20% · rate 6.9% · 30 yr$49,000
Gross monthly rent$2,150
Operating expenses (incl. vacancy, CapEx, maint.)$921
Monthly cash flow+$278
Cap rate6.01%
Cash-on-cash return5.7%
DSCR (lender test)1.26 — PASS
1% rule0.88% — FAIL
VerdictThin but viable — offer below ask

The workbook also works backwards: tell it the return you require, and it computes your maximum offer price.

What you get

One .xlsx workbook (6 tabs) + a written guide. Opens in Excel, Google Sheets or LibreOffice.

Tab 1 · Deal Analyzer

The 10-minute underwrite

Cash flow, NOI, cap rate, cash-on-cash, DSCR, GRM, 1% and 50% rule — each with a pass / warn / fail verdict written in English, not jargon.

Tab 2 · 30-Year Projection

What holding it actually earns

Rent growth, appreciation, loan paydown, equity and profit-if-sold for every year you hold.

Tab 3 · BRRRR Calculator

Cash left in the deal

Models the rehab and cash-out refi, then gives the only number that matters — how much of your money stays trapped, and whether you hit an infinite return.

Tab 4 · Stress Test

How bad can it get?

Cash flow across 9 rent levels × 6 vacancy rates, colour-coded, so you know your break-even before you sign, not after.

Tab 5 · Due Diligence

48 checks before you close

Numbers, physical, location, closing and rent-ready ops — including the "when to walk away" list. The sewer scope alone has saved buyers $10k.

Bonus · Written guide

The 10-Minute Underwriting Method

Step by step: where to get each number, which ones people fake, and the max-offer trick professionals use to price an offer instead of guessing at one.

Why this one and not a free download

Get the toolkit

One deal you don't buy pays for this a thousand times over.

$19$49LAUNCH PRICE
Secure checkout by Stripe · Instant download the moment you return · Refund on request, no questions

Questions

How is it delivered?

Instantly. Pay through Stripe, come back to this site, and the download page hands you the workbook and the guide straight away — nothing to wait for. Lost the tab? Go to /download and enter the email you used. Any trouble at all: [email protected], fixed or refunded the same day.

Do I need Excel?

No. It's a standard .xlsx — it opens in Google Sheets (free) and LibreOffice too.

Does it work outside the US?

The maths is universal — the checklist's tax and licensing items are US-oriented.

Is this financial advice?

No. It's a calculator and a checklist. The judgement is yours.