I am in the market for a used pop-up and have been able to go look at a few over the last couple of weeks. Much of what I read and get for advice says to stay away from anything with a leaky roof. A couple of the pop-ups I have seen have what looks like "bubbling" or "ripples" on the ceiling. No water stains, mold, or mildew, but those spots seem to be soft and swollen. I have read a few times that the layers in the ceiling will or have separated and some folks comment that this can happen over time and possibly occur do the high temps and which may allow the adhesives to fail. My question is, are those "bubbles and ripples" in a ceiling that feels soft a telltale sign of a leaky roof? Thanks for any help you can give. Also, I have been mostly looking at Coleman/Fleetwood pop-up campers from 2004 - 2010.