Being financially prepared is one of the smartest things you can do to help the home buying process run smoothly. Getting prequalified for a mortgage gives you an idea of what your loan program and the amount you could borrow might look like in advance. This can give you an advantage during the early-stage of your house hunt such as helping prepare your budget and setting your expectations.
Regardless of the loan amount you are prequalified for, stick to your budget and the amount you can comfortably afford. Your lender may pre-qualify you for more than you think you can comfortably afford. If this happens, you can always scale back to a lower loan amount.