The description of the cabover damage sounded worse than it looks in the pictures. It looks like it's nothing to worry about unless you really want to fix it for cosmetics. You could probably make your own cabinet doors pretty easily--that would really freshen up the look. I spray painted my camper white as well and I like it--especially since the truck is covered with the same paint. It looks like a decent buy to me. I picked mine up for $500 and it didn't have the water issues but it needed a fair bit of cleaning and freshening. It also didn't have a furnace and the fridge didn't look promising--I ditched it. Vinyl floor tiles are a great addition that are cheap and easy and really improve the look.
Have fun!
'85 4Runner & Four-Seasons Magnum pop-up