Guides · Real estate

Rent vs. Buy Math: Opportunity Cost & Unrecoverable Costs

'Renting is throwing money away' compares the whole rent cheque against nothing. Owning has money you never get back too — it's just spread across five line items instead of one, which makes it invisible.

Sources last verified 2026-07-21

Both sides have money you never see again

Rent is entirely unrecoverable: you pay it, you get housing, nothing accumulates. That much is true, and it's where the argument usually stops.

But most of an owner's monthly payment is unrecoverable too. Mortgage interest goes to the bank and never comes back. Property taxes, insurance, HOA dues and maintenance are all consumed. Only the principal portion moves money from one of your pockets to another, and early in a mortgage that portion is small — the interest share is largest at the start.

There's a fifth cost with no line item at all: the return your down payment isn't earning. Money locked in home equity isn't invested elsewhere, and over decades that forgone return is often the single biggest number in the comparison. It never appears on a statement, which is exactly why it gets left out.

Time horizon decides it more than the rate does

Buying and selling a home costs somewhere around 6–10% of the price in total — agent commissions, closing costs, title, transfer taxes. That's a fixed toll paid on the way in and out, and it doesn't shrink because you only stayed two years.

So a short horizon is close to decisive. Over two years, appreciation and principal repayment rarely cover a transaction cost of that size, and you can easily leave with less than you put in. Over ten or fifteen, the same toll is spread thin enough to stop dominating.

This reframes the question usefully. 'Should I buy?' is less about interest rates and prices than about how confident you are that you'll still want to live there in five to seven years. Flexibility is a real thing renting buys, and it's worth the most exactly when your life is least settled.