What Covered Wagon and HMS said is right on.
One place not mentioned is where the sewer drain access is. Using a flashlight look insdide and feel the walls.. There is part of the floor on the top of the door. Check that too for no sag and moisture damage.
I will mention again that my 2000 BF's vent over the door was a 12x12 vent, not a hatch.
I installed a 24x24 escape hatch that is metal framed.
The roof of these BF's are arched. The hatch can not sit flat. So I had to build up the roof with Butyl tape to compensate for the arch. As much as I tried to be careful tightening the hatch down to the roof the fiberglas arch flattened some and I ended up with a slight dip over time between the front of the hatch and the nose of the BF. That meant there was a bit of delam of the inside ceiling foam and wood inside roofing which is about 1/8". So I decided to live with the dip. That was 15 years ago.
The only leak I have had with my BF after I fixed a factory issues with a window was one from running light leak.
I do yearly maintenance for all the vents on the roof. I did replace one vent in the bathroom but not for a leak.
Oh, and if the roof vents for the black and gray tank little covers come off and it is raining water will end up inside the camper and from what I have found it will pool in the area of the sewer drain valve area. On my BF there is a little drain hole on the bottom of the camper where the valve access door is located.
The windows should all have a bit of butyl tape oozing out around the edges between the outside window frame and the fiberglass. If they do not inspect the separation and see how deep the cracks are. I had a great friend that had an 86 FB that was leaking from several windows due to this issue. He removed all the windows and resealed.
I discovered this issue after my camper was about a year old. I went around each window inside and lightly tightened the screws.... Some screws were totally loose... Boy did those window Butyl tape ooze. I trimmed it off.. 20 years later I still have a bit of butyl tape showing and no separation from the camper to window outside frame!
Hope this helps you... Our BF has almost 200,000 miles on it and has been on 2 trucks.
Jim
