You already know what you want: the lowest interest rate and smallest monthly payment possible. And you want to get it from a lender who is easy to work with and who will not hit you with any last-minute surprises or hidden fees.
Before you even start looking for a lender, you have to know what type of loan you are looking for. There are two basic types: fixed-rate and adjustable-rate mortgages, known as ARMs.
With a fixed-rate loan, the basic monthly payment -- interest and principal, not counting taxes, insurance or any assessments -- stays the same for as long as you have the loan.
With an ARM, the interest rate can change. When and how it changes will depend upon the type and length of the ARM you have. There are one-year ARMs, where the interest rate stays the same for the first year, and then changes based on where the index rate is on the date it changes. There are three-year ARMs, five-year ARMs and so on.