How Much House You Can Actually Afford

A lender's job is to determine the maximum they can safely lend you, not the amount you can comfortably live with. Those are different calculations aimed at different risks. The bank is protecting itself against default. Nobody in that chain is protecting you against a decade of feeling stretched thin in a home you technically qualified for.

This is the core of why HōMI exists: banks profit from speed, and the number they hand you is optimized for their approval process, not your actual margin. Treating a maximum-approval figure as a target is one of the most common ways people end up house-poor without ever missing a payment.

Debt-to-income ratio — your monthly debt payments divided by your gross monthly income — is the first filter any lender applies. Ratios at or below 28% tend to leave real breathing room. Between 28% and 36% is manageable but tighter. Above 43%, lenders themselves start hesitating, and above 50% is a hard line: it leaves almost no margin for a job change, a medical bill, or a bad month.

The math only tells you what's structurally survivable. It says nothing about whether you'll enjoy the life that comes with that ratio. That second question is yours to answer, and it's usually the one people skip.

A separate ratio worth tracking closely is your total monthly housing cost — principal, interest, taxes, insurance, and HOA dues — as a share of gross monthly income. When that share climbs high enough, the math stops being about comfort and starts being about risk: one bad month no longer dents your budget, it threatens the roof over your head.

This is one of the few places HōMI draws a firm line. When housing costs leave no room to breathe, the verdict turns protective regardless of how strong the rest of the picture looks, because no amount of emotional readiness offsets that exposure. We don't publish the exact line, so the signal can't be gamed.

A very small down payment isn't just a bigger loan — it's thinner equity, which means a soft market or a rushed sale in year two can leave you owing more than the home is worth. Twenty percent down remains the clearest marker of a purchase with real margin, but it's not a magic number; it's a proxy for discipline and cushion.

The emergency fund matters just as much as the down payment, and it's the one buyers most often ignore. Six months of expenses set aside, separate from the down payment, is what actually protects you once you own the surprises that come with ownership — the water heater, the roof, the year the property taxes jump. At the thin end, a single repair can start a debt spiral — and when there's essentially nothing set aside, HōMI stops treating it as a warning at all. The verdict turns protective, and the exact floor stays unpublished so it can't be gamed.

Take the lender's maximum, then build your own number backward from what you want your life to feel like after the purchase — the trips you still want to take, the savings rate you still want to hit, the buffer you want for the year something breaks. That number is almost always lower than the approval letter. It's also the only number that predicts whether you'll still like this decision in five years.