Rent vs. buy: the honest comparison

The most common mistake in a rent-vs-buy decision is comparing rent to the mortgage payment. That comparison feels intuitive, and it's almost always wrong. A mortgage payment is partly a forced savings plan (the principal) and partly a real cost (the interest). Rent is 100% cost. To compare them fairly, you have to strip the mortgage down to its actual expenses.

The four costs of owning that renters don't pay

• Mortgage interest — the portion of your payment that never comes back
• Property tax — typically 0.5–2% of the home's value each year
• Maintenance — a realistic reserve is around 1% of home value per year
• Insurance and, in many buildings, condo or HOA fees

Add those four up per month. That's the true 'cost to own' number. That's what to compare against your rent.

The cost renters pay that owners don't

If your down payment is sitting in a house, it isn't earning a return anywhere else. That's opportunity cost, and it's real. On a $100,000 down payment invested at a 5% real return, that's roughly $5,000 a year — about $415 a month — that owning quietly costs you. Ignoring it makes buying look better than it is.

A quick sanity check: the 5% rule

A useful back-of-the-envelope: take the home's value and multiply by 5% per year. Split that into three parts — roughly 1% property tax, 1% maintenance, 3% opportunity cost (or mortgage interest, whichever is your reality). Divide by 12. If that monthly number is lower than the rent on a comparable place, buying probably wins over the long run. If it's higher, renting is likely the better financial call — even if it doesn't feel that way.

A worked Canadian example: Toronto condo

A $750,000 downtown Toronto one-bedroom, 20% down. Mortgage: $600,000 at 5.5%, 25-year amortization → $3,660/mo. Property tax (~0.65% in Toronto) → $406/mo. Condo fees → $650/mo. Maintenance reserve (1% of value) → $625/mo. Insurance → $50/mo. Opportunity cost on $150,000 down at 5% real → $625/mo. All-in cost of owning: about $6,016/mo, of which roughly $2,750 goes to principal (savings) and $3,266 is 'true' cost. A comparable rental in the same building is often $3,000–$3,400/mo — meaning renting is competitive or even slightly cheaper in cash-flow terms, and the gap only closes with meaningful home-price appreciation.

A worked US example: Austin house

A $500,000 house in Austin with 20% down. Mortgage: $400,000 at 6.75%, 30-year → $2,594/mo. Property tax (~1.9% in Austin) → $792/mo. Insurance → $200/mo. Maintenance reserve → $417/mo. Opportunity cost on $100,000 → $417/mo. Total: about $4,420/mo, of which roughly $500 in year one goes to principal. Rent on a comparable 3-bedroom in the same area often runs $2,400–$2,900/mo. Owning costs $1,500–$2,000/mo more in true expenses — a gap that only pays off if the home appreciates faster than you'd invest that difference (historically about 3–4% real, on par with equities net of transaction costs).

The break-even horizon

Owning has huge upfront and one-time costs: land transfer tax, legal fees, inspections, moving, and on the sell side, real estate commissions (often 4–6% of sale price). These are dead-weight losses that get amortized over how long you stay. Under 3 years, almost no scenario favours buying — the transaction costs alone eat 8–12% of the price. Between 3–7 years is borderline and depends on the local market. Beyond 7 years, buying tends to win in most Canadian and US markets, especially when the principal you build acts as forced savings.

What actually changes the answer

• Down payment size — a larger down payment shrinks mortgage interest but raises opportunity cost
• Length of stay — the longer you stay, the more transaction costs amortize
• Local property tax rate — Texas at ~2% is a very different math from BC at ~0.4%
• Rent growth — cities where rents rise 5%+/year tilt toward buying; slow-rent cities tilt toward renting
• Whether you'd actually invest the savings — if the 'rent and invest' plan means 'rent and spend the difference,' owning wins by default

Frequently asked questions

Isn't rent 'throwing money away'? No more than mortgage interest, property tax, maintenance, and opportunity cost are. All of those are also money that doesn't come back. Rent just bundles them into one line item.

What about home appreciation? Historically, Canadian and US home prices have appreciated 3–4% per year in real terms over long horizons — roughly matching long-term stock returns after transaction costs. Betting on much more than that is speculation, not planning.

Does the mortgage principal count as savings? Yes — but only when you sell or refinance. Until then, it's illiquid equity. That matters if a job loss or move forces a sale in a down market.

The takeaway

Rent vs. buy is a math problem before it's a lifestyle one. Do the math with all the costs on both sides, and the honest answer usually surprises people — in both directions.