Do as much of the prep work as you can. Trim removal and reassembly can be expensive when you can do most of it yourself. Get referrals and actually look at the work that has come out of the shop, then make sure you get the same guy. Do a walk through of the shop and look closely at the conditions and works in progress. Your gut should tell you if a place is right and will do good by you.
And no matter what anyone says to you, your only claim is to what they are willing to put on paper. If they are good, they won't hesitate to commit.
You're going to be spending a lot of money, research research research.