This is a common question I get a lot and the answer is simple....Both...In order to buy a home you need to have good credit and nice income. A lender will use these two criteria's as well as how much money you have saved when they do their pre approval process. They want to see what your payment history is to make sure you will be reliable when it comes to paying the monthly mortgage back to the lender who financed the home. So good credit is so important for everyone on the loan because it will also help determine the interest rate you will be eligible for. The reason for good income is because they want to make sure you can afford the payment also. They check what they call a debt to income ratio to see how much are your current expenses and then add what your mortgage payment would be, then compare that to your income to see if you make enough money to carry those expenses. This is why I say the answer to this question is Both because the better you are in both situations the better approval you will get from the bank.