moderator: thanks for the move
Terry-you are mostly incorrect in your assessment. The real problem was coachman's build. At the edge of the membrane on the slideout; there is a 13' long horizontal seam. Grass hut builders use shingling where coachman used caulk. I did realize delam, but assumed it was from the missing trim-which fell off from the rot-duh on me...I'll work on a pic for you a week from today.
And no paint bubbling, but loose filon. The filon curve on the back is never tight, so I assumed it did not matter on the front.
As for crediting me, that was never the request-to critique my purchase. The guy that bought it a year ago took a $2800 hit-I asked him to come clean on price after finding all the rot.
Why would I use a waterproof plywood? The camper should never be wet inside the wall.
As for the two layer build up. There is lots of good adhesion on the filon, so removing it is not very wise and would probably result in damage to the filon. I am mostly looking for the best adhesive and not a big fan of contact for the obvious difficulty of can't move it.
I appreciate the less glue idea. I think I will use some open time adhesive and stick with mechanical fasteners.
Thanks to all.