• Income ratio: Your total monthly housing expense divided by your pre-tax monthly income.
  • Debt ratio: Your total monthly housing expense plus any recurring debts, i.e., car payments, monthly minimum credit card payments, and other loan payments, divided by your monthly income.
  • Standard loan underwriting guidelines suggest a max 28 percent income ratio and 36 percent debt ratio, which may vary based on personal finances, loan program, and down payment.

While not taking on any debt and paying for everything with cash seems like a logical choice if you feel you can’t afford your lifestyle, no credit also means bad credit in the eyes of a lender. There’s bound to be a time when you can’t buy something with cash, like buying a house (in most cases). So, we recommend opening at least three credit card accounts and making occasional purchases.

To manage your debt and maintain healthy credit, keep credit card balances to less than 30 percent of your credit limit. Also, don’t close long-term credit lines, even if they’re not being used. Your longest-standing credit card account might be a huge contributor to your credit score health — and the mortgage rate you qualify for.