It's not involved, providing there are no unforeseen problems, it can be done in 45 minutes. There are 7 screws to remove, 2 in the one sideplate for inspection, 1 wood screw in the trigger guard (providing it is a 1 screw guard), 3 in the trigger plate housing, and 1 screw under the top lever. The hardest is the one small screw (4-40 thread) that goes to the top lever shaft when you go to put it together. I don't have any idea what a gun smith would charge.