Where our numbers come from
From data: the interest rate is Freddie Mac's weekly average for the week of Oct 15, 2026. Property tax uses your county's or district's rate, the homestead exemption and Oklahoma's 3% cap on yearly value increases. Insurance starts at Oklahoma's average, $5,298 a year.
Your guesses: rent growth, home value growth, investment return, upkeep and the cost to sell. They start at 3%, 3%, 5%, 1% and 6%. Those are round starting points, not forecasts. Our first-year cost guide sets the 1% upkeep guess next to Census figures on what owners spend.
Rent: You enter it. A county average wouldn't describe the place you'd actually rent.
Worked example: what owning costs in the first month
Take the starting inputs: a $250,000 house with 10% down in district code 200 (Oklahoma City schools), at 7.40% for 30 years. Owning costs about $2,592 in the first month. That's $1,558 of principal and interest, plus property tax, insurance, PMI and 1% a year for upkeep.
If your rent is well below that, renting stays cheaper for years. Close to it, the answer turns on your guesses about home values and investment returns.
How the comparison works
Both paths get the same budget each month, and the cheaper one invests the difference. The renter also invests the cash the buyer puts into the down payment and closing costs. At the end of each year we ask what each path cost if you stopped there.
Net cost is the cash you put in minus what you'd walk away with. For a buyer, that's the sale price after selling costs, minus the loan, plus savings. For a renter, it's the savings. The lower net cost wins, and the break-even year is the first year buying does.
Reading the result
How long you stay matters most. Buying has big one-time costs, closing now and selling later, and the longer you stay, the more years they're spread over. Change the value growth and investment return by a point or two and watch the break-even year move.
What the model leaves out
Income taxes are left out: the mortgage interest deduction, tax on investment gains and any tax on the sale. So are renter's insurance and moving costs. The first year's property tax assumes the assessor values the home at the price you pay. For the full payment on one house, use the mortgage calculator.
Questions
Why do I have to enter the rent?
Because the right number is the rent for a place like the one you'd buy, which no county average captures. We also haven't loaded HUD or Census rent data, since both need API accounts.
Are the appreciation and investment return predictions?
No. They're round starting points, labeled as your guesses. Nobody knows future returns, so try a few values to see how much the answer moves.
What does net cost mean?
The cash you put in over the years minus what you'd have at the end. For a buyer, that's the sale price after selling costs, minus the loan, plus savings. For a renter, it's the savings.
Does the model include Oklahoma's property tax cap?
Yes. Taxable value grows with the home's value, but no faster than 3% a year with a homestead exemption (5% without), under Oklahoma Constitution art. 10, § 8B.
Sources
- Freddie Mac, Primary Mortgage Market Survey® history (CSV) (Oct 15, 2026; retrieved Oct 19, 2026)
- Oklahoma County Assessor, Oklahoma County Tax Rates/Millages for 2025 (Nov 17, 2025; retrieved Oct 8, 2026)
- Oklahoma Tax Commission (OTC), Ad Valorem Division, 2024 Ad Valorem Statistics (2024; retrieved Oct 8, 2026)
- LendingTree, State of Home Insurance: 2026 (Jun 8, 2026; retrieved Oct 8, 2026)
- Freddie Mac (My Home), Breaking down PMI (Oct 8, 2026; retrieved Oct 8, 2026)
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