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Do the math before the mortgage.

17 honest calculators, a seven-stage buyer course, plain-English answers, and an AI that decodes the paperwork — every assumption shown, every number checkable.

✓ Built by lenders. Priced like a library: $0.

Your real monthly payment

Principal & interest$2,497
Property taxes$230
Insurance$150
PMI (until 20%)$198
All-in monthly$3,075
✓ checked — tap to run yours
What's inside

Four rooms, all open.

Buyer academy

The complete seven-stage journey from "am I even ready?" to keys in hand. Each stage: a plain-English explainer, what can go wrong, a checklist, and the questions to ask.

Enter the academy →

Calculators

Seventeen honest money tools for every seat at the table — buyers, owners, sellers, and the agents guiding them — with assumptions shown, not hidden.

Run the numbers →

AI concierge

Paste any confusing paragraph — from an inspection report, loan estimate, or contract — and get it back in plain English. Or just ask a question about the process.

Decode a document →

Glossary

Escrow, PMI, contingency, earnest money — the whole confusing vocabulary of real estate and lending, decoded into sentences a human would say.

Decode the jargon →
Coming soon: a down payment assistance directory, Agent HQ with co-brandable client kits, and the post-close Owner hub with a maintenance calendar and yearly equity snapshots.
Why it's free

The house rules.

Everything is a give

No gated PDFs, no "enter your email to see the answer." If it's here, it's yours. We'd rather earn trust than capture leads.

Plain English, always

If a sentence needs a law degree to parse, we rewrite it. Buying a home is stressful enough without the vocabulary test.

Humans on call

Every tool ends the same way: if you want a real person to look at your situation, that person is Gavin — a licensed broker, not a call center. Meet him →

Buyer academy

Seven stages. Zero mystery.

Work through the journey in order, or jump straight to wherever you are. Every stage is live.

Calculators

Run the numbers, keep the assumptions.

The two numbers everyone needs, right up top. Fifteen more below when you’re ready to go deeper. Every assumption is visible, and nothing here asks for your email.

Start here

True monthly payment

The full PITI picture — principal, interest, taxes, insurance — plus HOA. The listing price never tells you this.

All-in monthly
$—

per month, everything included

Principal & interest—
Property taxes—
Insurance—
HOA—

Closing cost estimator

The check you write at the table beyond your down payment — typically 2–5% of the price. Here's the honest range, itemized.

Likely range
$—

estimated total closing costs

Lender fees (origination, underwriting)—
Title & escrow services—
Appraisal & inspections—
Prepaids (taxes, insurance, interest)—

Your Loan Estimate (delivered within 3 business days of applying) replaces this with exact figures. Some fees are shoppable — ask which.

Advanced calculators — for when you want to go nuts
Getting ready
Making the offer
Owning
Selling & moving up

What can I afford?

Uses the classic 28/36 rule lenders start from: housing under 28% of gross income, all debts under 36%.

Your comfortable range
$—

Estimated max home price

Monthly housing budget (28%)—
Room after other debts (36%)—
Estimated loan amount—
+ your down payment—

Assumes ~22% of your housing budget goes to taxes and insurance. A pre-approval will sharpen this into a real number.

DTI checker

See your debt-to-income ratio the way an underwriter does — before an underwriter does.

Your ratios
—

Front-end (housing ÷ income)—
Back-end (all debts ÷ income)—

Rules of thumb: front-end under ~28% is comfortable. Back-end under 36% is strong, 36–43% is common approval territory, above ~45% gets hard. Programs vary.

Debt payoff priority

If you can only pay off one debt before applying, which helps your approval most? Underwriters care about monthly payments, not balances — so the answer is often surprising.

Pay this one first
—

The metric: monthly payment freed per $1,000 of payoff. Small balances with big minimums (hello, credit cards) usually win. Debts within ~10 months of paid-off can sometimes be excluded anyway — ask your lender before spending a dime.

Down payment savings timeline

Turn "someday" into a date on the calendar.

Your target date
—

Months to goal—
Interest earned along the way—

Tip: a high-yield savings account, automated on payday, is the whole strategy. Boring wins.

Rent vs. buy

A simplified head-to-head over your time horizon: total cost of renting vs. owning, counting the equity you'd build.

Over your horizon
—

Total rent paid—
Total ownership outlay—
Equity + appreciation built—
Net cost of owning—

Ownership outlay includes payments, ~1.6%/yr taxes-insurance-upkeep, and ~8% buy/sell transaction costs. Simplified on purpose — the trend matters more than the decimals.

Cost of waiting

What does "we'll wait a year" actually cost if prices keep drifting up and rent keeps going out the door?

The price of patience
$—

Same house, later price—
Price increase—
Rent paid while waiting—
Monthly payment then vs. now—

Waiting is sometimes right — to save more, fix credit, or steady a job. This tool just makes the trade visible instead of invisible. Appreciation isn't guaranteed.

FHA vs. conventional

The classic first-timer fork in the road, compared at the same price: FHA's easier entry vs. conventional's cancellable PMI.

Monthly, side by side
—

FHA: P&I + monthly MIP—
Conventional: P&I + PMI—
FHA upfront MIP (financed into loan)—

The long-game difference: conventional PMI cancels at ~20% equity, while FHA's MIP usually lasts the life of the loan when you put under 10% down — many FHA buyers later refinance out of it. Rates and MI factors vary; have a lender price both for you.

Offer structure analyzer

Higher price with seller-paid closing costs, or a clean lower offer? Both can net the seller the same — but they treat your wallet very differently.

Head to head
—

Cash to close — A vs. B—
Monthly P&I — A vs. B—
Seller's gross net — A vs. B—
5-year total outlay — A vs. B—

The pattern: credits preserve your cash today in exchange for a slightly higher payment forever. If cash-to-close is your constraint (it usually is), the "higher price + credit" structure often wins. Credits are capped by loan program — ask your lender.

Temporary buydown (2-1, 1-0, 3-2-1)

A seller or builder credit pre-pays part of your interest, lowering the payment for the first years. See each year's payment and what the subsidy really costs.

Payment by year
$—

Total buydown cost (the credit needed)—
Same credit as a price cut would save—

Temporary buydowns are usually funded by seller or builder credits, not your cash. Compare against a permanent rate buy-down and a price reduction before choosing — your lender can price all three.

Cash to close

The actual check: down payment plus closing costs, minus what you've already put in and any credits.

Bring to the table
$—

estimated cash to close

Down payment—
+ Closing costs & prepaids—
− Earnest money (already in escrow)—
− Credits—

Your Closing Disclosure will state this to the penny. Funds usually must be wired or a cashier's check — verify wire instructions by phone, always.

Extra payment impact

What a little extra principal every month does to a mortgage. Spoiler: it's the most boring wealth hack in existence.

The payoff
—

Interest without extra payments—
Interest with extra payments—
Paid off sooner by—

Make sure extra payments are applied to principal (tell your servicer). And fund your emergency savings and any high-interest debt first — the mortgage is usually your cheapest debt.

PMI removal date

Between paying down the loan and the home appreciating, when do you hit 20% equity — and what does dropping PMI save?

Freedom date
—

Months until 20% equity—
PMI paid until then—
Yearly savings after removal—

Removal isn't always automatic before 78% of the original value — if appreciation gets you to 20% early, you typically must request removal and may need an appraisal. A phone call worth hundreds a year.

Points & refi breakeven

Paying money up front to lower your rate — points now, or a refinance later — only wins if you keep the loan past the breakeven date.

Breakeven point
—

5-year net result—
10-year net result—

If you might sell or refinance again before the breakeven date, keep your cash instead.

Seller net sheet

For sellers (and their agents): the number that actually matters — what you walk away with after everyone's paid.

Walk-away number
$—

estimated net proceeds

Sale price—
− Mortgage payoff—
− Commission—
− Title, escrow & transfer—
− Taxes, concessions & repairs—

Payoff amounts include per-diem interest, so request an official payoff quote from your servicer. Local transfer taxes vary a lot — your title company can pin these numbers down.

Move-up budget

Selling and buying again? Chain your net proceeds into your next purchase and find the price range that keeps the payment comfortable.

Your next-home range
$—

estimated next purchase price

Net proceeds from sale—
+ Extra savings—
= Down payment power—
+ Loan your budget supports—

P&I only — add taxes and insurance with the payment calculator for the full picture. Timing the sell-then-buy dance (contingent offers, bridge options, rent-backs) is where a good agent earns their keep.

These calculators are educational estimates, not loan offers or financial advice. Rates, taxes, and program rules vary — a licensed professional can turn these ranges into real numbers for your situation.

AI concierge Beta

Confusing document? Paste it here.

Inspection reports, loan estimates, contracts — they're written for lawyers, not humans. Paste any paragraph and get it back in plain English, or just ask a question about the process.

Your plain-English answer will appear here. Nothing you paste is saved by this site.

The concierge explains — it doesn't advise. For decisions about your specific transaction, loop in your agent, lender, or attorney. Answers are AI-generated explanations and can be imperfect — the professionals on your deal always have the final word.

The human behind the math

Hi, I'm Gavin.

I'm Gavin Guthrie — mortgage broker and owner of The Mortgage Collective, serving Arizona and Utah. I built BuyerMath because the mortgage world profits from confusion, and I'd rather compete on clarity: show people the real math, give the good stuff away, and earn trust the honest way.

Everything on this site is free and stays free — no email walls, no fine-print catch. And when you're ready for a human to look at your specific numbers, that human is me. A 15-minute "where do I stand?" call costs nothing and isn't a test you can fail.

Gavin Guthrie

Mortgage Broker / Owner · NMLS #928960

Phone480-297-9421
Emailgavin@mymortgagecollective.com
Office7257 S. Atwood, Ste 106, Mesa, AZ
ServingArizona & Utah
CompanyThe Mortgage Collective

Company NMLS #2469778 · AZ Mortgage Broker License #AZMB-2008586 · Equal Housing Opportunity

Privacy

The short, honest version.

BuyerMath is a free resource. Here's exactly what we collect and why — in the same plain English as everything else here.

What we collect

If you send a game-plan request: the name, email, and notes you type — used only to reply to you. No newsletters you didn't ask for, no selling your info. Ever.

Browsing data: like most websites, we may use analytics and advertising cookies (such as the Meta Pixel and Google tags) to understand which tools people find useful and to show BuyerMath to visitors again on other platforms. These identify your browser, not your name.

What we never do

We never sell your information. We never share your game-plan details with anyone outside the team that replies to you. Calculator inputs stay in your browser — the numbers you type are never transmitted or stored by us.

Your choices

You can browse everything here without submitting anything. To limit ad cookies, use your browser's privacy settings or the ad-preference tools at Meta and Google. To have a submitted request deleted, email us and it's done.

Contact

Questions about any of this: gavin@mymortgagecollective.com. BuyerMath is operated by The Mortgage Collective (Company NMLS #2469778 · AZ Lic. #AZMB-2008586).

This page is a plain-language summary, last updated August 2026. It isn't legal advice — have your compliance or legal advisor review it before relying on it.

Glossary

Jargon, decoded.

Every term below is explained the way a friend would — one who happens to know real estate cold.