2000 Holiday Rambler endeavor 38'
IMO, the major weak points of this design are the roof/wall seams, slide seals, and huge hidden holes in the house structure where rodents can enter. I would try to address them in that order, so that yours doesn’t end up looking like mine. And believe the owners manual where it says not to allow snow to accumulate on the roof.
2000 HR Endeavor 40PBD, Freightliner XC, CAT 3126B