Getting prequalified can be a helpful first step in the home buying process. Prequalification involves answering a few questions about your financial situation, after which a loan officer will tell you whether you might be mortgage-qualified and what your maximum loan amount is likely to be. Mortgage preapproval, on the other hand, is a more rigorous process that involves supplying financial documents and going through a credit check and underwriting. After this, you’ll have a verified approval and know your final loan amount and interest rate. Preapproval is often required to make an offer on a house.