We have a 21 foot 1994 Gulf Stream Conquest Limited Edition motorhome with a coach leakage problem in the back wall area when it rains. Water drips out underneath the bottom of the right side taillight assembly, and there is a delamination bubble in the rear outside wall about a foot to left of (but not touching) the rear window. On the inside, the head of the mattress where it abuts the back wall, will become soaking wet. When camping, we slightly elevate the back end of the coach for comfortable sleeping purposes, so the coach is not perfectly flat. When the motorhome is moved, water will come out of the bottom corner curb side/back wall. So far we have caulked every possible outside joint, rear window, taillights, ladder supports, and the running lights. Inside we caulked the back wall seam that the head of the mattress touches. We have closely inspected the roof and roof edges and found no visible leaks. There are no visible water stains anywhere inside the coach. As a last resort, we've made an appointment to have the entire roof replaced next week, but we are reluctant to proceed with it because of the age of the roof-top items that will have to be removed then reinstalled. Replacing this motorhome is not an option for various reasons.