According to the 28% rule, if you're making $70,000 per year, you shouldn't spend more than $1,633 each month on your mortgage. How much house this translates to depends on your down payment, your interest rate, and how much you pay in taxes and insurance. For example, if you make a 3% down payment, have a 6% rate, and spend $300 per month on taxes and insurance, you might be able to afford a $225,000 home on a $70,000 annual salary.