If you know that you will be moving in 3 to 5 years, you might want to consider refinancing to a 3 or 5 year ARM (adjustable rate mortgage). These loans typically have a much lower rate that a traditional fixed rate loan such as a 30 year fixed, but they do have a fixed rate for the first 3 or 5 years of the loan. This will enable you to benefit from the lower rate, but you won't ever have to worry about the risk of a rate adjustment because you will be selling the home before the fixed-rate period ends.
When evaluating different lender offers, in the mortgage loan pre-approval process, pay closest attention to the interest rates they are offering & the closing costs. These are the two biggest factors that will help you figure out which lender is right for you. If one of these two factors is too high, it could offset the benefit of refinancing for you.
Weigh the costs carefully of how long you will be staying in your home vs. how much of a savings you will be getting in a refinance. Make sure you include closing costs in your decision.
These days most people request a Good Faith Estimate (GFE), but have no clue what to look for on the GFE. Make sure you request a GFE that has ALL fees estimated and disclosed. This includes: origination points, processing, lender, appraisal, title, escrow... ALL FEES... especially the Yield Spread Premium or YSP.