I just recently found out how expensive it can be. Tail swing getting out of a tight spot caught the curb side corner of the rear cap on a post and pulled it back about two feet tearing the fiberglass cap in three places. Pulled away from the rear window, but did not break it. And some scrapes on the side panel. Rear cap had to be completely removed to repair the damaged fiberglass and then painted. Then reinstalled, recaulked, and new decals/graphics. Washed entire 5er including roof and awning. Final tally about $16k! But they did a fantastic job handling the estimate, coordinating with my insurance, and completing the entire process in 3 weeks. Rear cap looks better than new.
Might have found a cheaper shop somewhere, but my insurance had no problem with the number and paid in full, no questions asked. Your damage may not be as bad.