I've looked at hundreds of used RV and it's completely normal. The Cameo is no different than any other brand if it hasn't been maintained. I do believe a lot of water damage can end up on dealer lots. Some people will lie like crazy and sell privately and some don't want to deal with that so they trade at a dealership.
I have climbed on and in and under dealership rigs with severe damage and wondered why in the world they would sell it to anyone. Well actually that water damaged rig can be a gold mine. They sell it and are then more than happy to take it back and give you every penny back towards a new rig. For them the beauty of that arrangement is that they now have a captive buyer that is much different than the guy who walks in and says he'll pay X amount and goes back home to wait for a call from the dealer saying they will accept or certainly do better on the price.
Those are two completely different buyers. One holding all the cards and the other with none.