Rent vs. Buy: The Real Math Most People Get Wrong

"Rent is throwing money away" is one of the most expensive pieces of bad advice in personal finance. Buying can be a great move — but only when the math actually works for your timeline. Here is how to run the real comparison in 10 minutes.

The hidden costs of owning

The "mortgage vs. rent" comparison most people make is wrong because it leaves out everything except principal and interest. The full cost of owning includes:

• Property tax (0.5–2.5% of home value per year)
• Homeowners insurance ($1,500–$3,500/year average)
• Maintenance (rule of thumb: 1% of home value per year)
• HOA fees (condos and many neighborhoods)
• Closing costs (2–5% on purchase, 6–10% on sale)
• Opportunity cost on the down payment (what it would have earned invested)

The Mortgage Calculator includes property tax and insurance so you see the true monthly cost — not just principal and interest.

The 5-year break-even rule

The simplest rule of thumb: do not buy unless you plan to stay at least 5 years. With ~6% closing costs on the way out, anything shorter usually loses money to transaction costs alone — even in a hot market.

The complete break-even formula

You also need to credit renting with the opportunity cost of investing your would-be down payment. $60,000 invested at 7% for 5 years grows to ~$84,000 — that growth is what renting "earns" you in the comparison.

Worked example

Over 5 years that owning premium totals ~$48,000. To break even, you need price appreciation + equity built > $48,000 + closing costs (~$30,000) + opportunity cost on the $60,000 down payment (~$24,000 in foregone returns) = ~$102,000. At a typical 3% appreciation, $400k grows to ~$464k — a $64k gain. Renting wins this scenario by ~$38k, despite "throwing money away."

When buying clearly wins

• You will live there 7+ years.
• You can put 20% down without draining your emergency fund.
• The owning premium over local rent is under 30%.
• You actually want the lifestyle (yard, pets, customization, school district).
• Your job is stable and tied to the area.

When renting clearly wins

• You will move within 5 years.
• The local price-to-rent ratio is over 21.
• You would buy with less than 10% down.
• Your career or relationships are in flux.
• You would invest the difference rather than spend it.

The under-discussed scenario: rent and invest

A renter who consistently invests the owning premium often comes out ahead. Plug your numbers into the Compound Interest Calculator: $800/month at 7% for 30 years compounds to roughly $980,000. That is not "throwing money away" — that is a near-millionaire retirement.