There is a big difference between a buyer being pre-qualified and a buyer who has a pre-approved loan. Anyone can get pre-approved for a loan. However, getting pre-approved means a lender has looked at all of your financial information and they've let you know how much you can afford and how much they will lend you. Being pre-approved will save you a lot of time and energy, as it gives you the opportunity to shop around for the best deal and the best interest rates.
