 which is to first have a thousand dollars saved as a starter emergency fund, then second become debt-free everything but the house using the debt snowball, third build an emergency fund of three to six months of expenses, and then fourth start investing 15 percent of your income. In your case if you had no payments but a house payment and you save 15 percent of your income, 15 percent of $40,000 is $6,000, that's $500 a month.