Banks are not the best place to get a mortgage any more. In general their guidelines are more restrictive than if you went to a mortgage lender that only originates mortgage loans and doesn't do any other banking services. These types of companys are referred to as "non-bank" lenders. Work with an experienced mortgage LO that knows what s/he is doing so you can ask all of your questions and get appropriate answers. You will have the best results if they originate, underwrite and fund their own loans. Many of the CU's today actually pass the mortgage apps off to someone else to process.
Big box banks have some decent LO's but most seem to have dissappeared over the last ten years so it is really hit or miss unless you are seeking a jumbo loan. At all costs - stay away from Wells Fargo. They are known to issue a pre-approval (same with BOA) easily but when it comes time to close the loan, they issue a denial. It is very frustrating (I'm a Realtor). In my area you hurt your chances of getting your offer accepted if you submit a pre-approval from any of the big box banks like Wells Fargo, Chase or BOA.
I know I am sweeping with a broad brush. It is really best if you speak to your Realtor and your friends and family to find out who they used that they were satisfied with - a personal referal is the best way to go. If they don't have one to recommend to you then come back and I will pm a couple of excellent LO's that can get the job done right.
