Start with a comfortable payment, not a maximum approval
A lender can tell you the largest payment it may approve under its rules. That number is not the same as a payment that leaves you comfortable month after month. Your own budget has to absorb not only housing, but food, transport, childcare, travel, repairs, and goals that matter to you beyond the house itself.
Think in layers, not one mortgage number
| Layer | What belongs here |
|---|---|
| Mortgage payment | Principal and interest. |
| Housing overhead | Property taxes, homeowner's insurance, HOA dues, PMI if applicable. |
| Ownership reality | Maintenance, repairs, furnishings, utilities, and periodic surprises. |
| Life outside the house | Savings goals, retirement contributions, childcare, travel, and debt payments. |
If the house only works when you ignore the bottom two rows, it probably is not truly affordable.
Keep margin for a bad month, not just a good month
Affordability should survive ordinary setbacks: a car repair, one expensive month, a slower bonus season, or the reality that a new home always seems to reveal one more cost after move-in.
Buyers with variable income, thin cash reserves, or large upcoming life changes should treat affordability more conservatively than buyers with stable income and a stronger emergency fund.
Three scenarios worth testing
- Base case: your realistic home price, down payment, and current rate.
- Stress case: the same home with a rate that is 1 point higher.
- Cash-preserving case: a slightly smaller down payment that leaves a healthier reserve after closing.
Do not forget cash to close
Many buyers focus so hard on the monthly payment that they overlook the transaction itself. A house can look affordable on paper and still feel financially destabilizing if it empties your cash at closing.
Use the cash to close guide before assuming a larger down payment is always the safest option.