You have three potential areas of concern which may or may not have been corrected by the previous owner. These areas are covered by Tiffin and will be repaired if you have them. You can call Tiffin, have the VIN number handy, and see if any of these repairs have been made.
1. Roof rails - the symptom is very fine cracks in the radius portion of the roof. If it has been repaired, you will see a row of rivets (covered by Dicor) running from front to back along the edge of the flat portion of the roof.
2. Wet bay floor - You can check this by using an awl to test the floor underneath the coach. If the awl penetrates easily, you will need to have this inspected further. Also, if the front of the bay and the floor is lined with gray plastic material, the repair has been done.
3. Driver's side front slide floor - from the outside with the slide extended look at the bottom of the slide. If it is metal, it has been corrected, it is plywood, use the awl to test for softness, especially the front of the slide.
You can have these repairs done at Red Bay, or a couple of other locations. You can ask Tiffin for alternate locations.
These are about it for known problems.
Roger & Mary
2014 Tiffin Phaeton 36GH
2012 Honda Fit toad