As a relativly new RVer I am learning these lessons. I will never take my coach to the dealer for work ever again.
The coach batteries would never charge on shore power, and the coach had a leak in the cab area. 2 of the screws that hold the trim just above and in front of the door on our last outing (before we took it in for the IOU stuff) and you could see behind the side wall. I duct taped over it to attempt to keep the rain out.
We had done some troubleshooting before we took it in and determined that the 110 charger output was not getting to the coach batteries. The dealership replaced the batteries and called it good, then siliconed the snot out of the running lights and said the leak was fixed. When I picked it up 3 weeks after we dropped it off it still had the tape on the trim that I put on.
The smartest thing I have done since I bought the coach was join FMCA & then get involved with a local chapter. (The Pudget Sounders)
One of the members lives about 45 minutes away from me & he has let me keep it in his garage while we work on it. He correctly diagnosed & fixed the bad 50 amp breaker that was the real charging problem, and we are in the process of replacing the plywood that delaminated while the coach was sitting outside at the dealership. Lucky for us it is the narrow strip between the front door & the front cap.
While we're at it I'm re calking everything just to be on the safe side.