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IMO you need to locate a good mortgage broker in your area. The broker can shop around for you without multiple pulls on your report.
It turns out that my LO was much better at working for us than I originally thought she would be. She worked with the UW's to make sure we could get an exception for open lines of credit and then I ran into a potential appraisal problem that she helped us out with. Apparently living in a small rural county makes it hard to get an appraisal on a Berm house but everything has worked out and we put an offer in today. Since we have had to talked to the UW's several times and the appraiser once I am feeling pretty confident that things should work out well going forward.