Start with income and existing debt
Lenders size affordability mostly through your debt-to-income ratio — how much of your gross monthly income already goes to debt. A common rule of thumb keeps housing near 28% of gross income and all debt under about 36%, though every program and lender bends those lines.
Price the whole payment, not the loan
Affordability is about the full housing payment, not just principal and interest. Add property tax, homeowner's insurance, mortgage insurance if your down payment is thin, and any HOA dues. Two houses with the same sticker price can carry very different monthly costs once the tax bill lands.
| Gross monthly income | 7,000 |
| Target housing payment (28%) | ~1,960 |
| Est. taxes + insurance | ~400 |
| Room for principal & interest | ~1,560 |
What the down payment buys you
A bigger down payment shrinks the amount financed, can knock out mortgage insurance and lowers the monthly payment — every one of which lets a fixed budget reach a higher price. It also hands you more equity on day one, which matters the moment prices move the wrong way.
Leave room for the rest of your life
A lender's maximum assumes nothing about your savings goals, childcare, travel or the irregular bills that always come. A payment that technically qualifies can still squeeze everything else flat. Aim below the ceiling, at a payment that still lets you save and absorb a surprise.
A working sequence
- Set a comfortable total housing payment from your income.
- Subtract estimated tax and insurance to find what's left for principal and interest.
- Work back to a loan amount and price using your expected rate.
- Stress-test it — would the payment still hold if your income dipped for a few months?
The number a lender approves and the number you can comfortably live with are rarely the same. We'd treat the approval as a ceiling to stay well under — the lender's math ignores your savings goals, childcare, and the months your income dips.
Frequently asked questions
What percentage of income should go to housing?
A widely used guideline is around 28% of gross income for housing and under about 36% for all debt, but comfortable limits depend on your other expenses.
Does a bigger down payment let me afford more?
Yes. It lowers the financed amount and can remove mortgage insurance, so more of your budget buys house rather than financing costs.
Should I borrow the maximum the lender offers?
Usually not. The maximum rarely accounts for savings and lifestyle costs; a payment below the ceiling is safer.
Do taxes and insurance really change affordability?
Significantly. They can add hundreds per month and vary a lot by location, so always include them in your estimate.
Affordability here uses the common payment-to-income guidelines (roughly 28% for housing, 36% for total debt). Your lender applies its own limits and may allow more or less.
This is general information, not personalised financial, tax or lending advice. The real terms come from your lender; confirm every figure on an official offer before making a decision.