Two answers: what a lender will approve, and what your budget can genuinely sustain. Preloaded with Montana averages — edit any field to match your situation.
Maximum home price
$243,428
What a lender would likely approve using the 28/36 rule.
Housing held to 22% of gross income.
On $69,000 of gross income with $550 of existing monthly debt, the 28/36 rule supports about $1,520 a month toward housing. With $56,000 down at 6.65%, that reaches roughly $243,428 — a $187,428 loan at 23% down. Your resulting debt-to-income ratio would be 36%, and you are currently limited by the total debt.
The 28% ceiling assumes no childcare, no aggressive retirement saving, and stable income. Holding housing to 22% of gross income — about $1,265 a month — supports roughly $207,187 and leaves $255 a month for retirement contributions, maintenance and the irregular costs that arrive every year. Buyers who stretch to the maximum are the ones who stop contributing to retirement.
A $207,187 home means roughly $1,265 a month all-in. Run it through the mortgage calculator to see the full breakdown, and check the rent vs buy comparison if there is any chance you move within five years.
Full payment breakdownMontana has an effective property tax rate of about 0.74% of home value, which on the statewide median price of $465,000 works out to roughly $287 a month before you touch principal or interest.
Homeowners insurance averages about $2,000 a year here, or $167 a month. No general sales tax.
The top marginal state income tax rate is 5.9%, which reduces take-home pay and so lowers the payment a lender will approve. The calculator above starts from these statewide figures — replace them with your actual county's rate and a real insurance quote as soon as you have them.
State figures are statewide averages used as starting values for the calculator. They are estimates for modeling only — not quotes, appraisals or tax advice. Your county, city, lender and insurer will differ. Edit any input to match your situation.
With no other debt and a 10% down payment at current rates, roughly $250,000–290,000 under the 28% rule, depending on your property tax rate. A more comfortable target that preserves retirement saving is closer to $200,000–235,000. Existing car or student loan payments reduce both figures substantially.
At 6.65% with 10% down, a $400,000 home costs roughly $3,100 a month all-in. The 28% rule implies about $133,000 of gross household income to support that comfortably, or around $105,000 if you stretch to the 36% back-end limit with no other debt. In low-property-tax states the requirement drops by several thousand dollars of income.
Indirectly, through the interest rate you enter. Credit score's main effect on affordability is the rate you are offered — the difference between a 680 and 760 score is commonly 0.4–0.6 percentage points. Enter a realistic rate for your score rather than the best advertised rate, since advertised rates assume excellent credit and substantial down payments.
Include it if both of you will be on the loan. If only one spouse applies, only that income counts — but the lender still counts both spouses' debts in community property states. Applying with one borrower is sometimes worthwhile when the other has poor credit, since lenders price from the lower of the two scores.
Closing costs of 2–5% of the purchase price, plus an intact emergency fund of three to six months of expenses, plus a moving and immediate-repairs buffer. On a $400,000 home that is roughly $10,000–20,000 in closing costs on top of the down payment. Arriving at closing with nothing left is the most common avoidable mistake in home buying.
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