We have not had any issues. During the summer it sits on a concrete driveway, plugged in. Winter it's in a barn, and the farmer has lots of cats.
I have an open underbelly. There are lots and lots of j oles to be found. I used copper mesh and marine caulk. Filled every hole I could reach from the top and bottom.
As for the hose coming from the fw tank. Ours has two pieces of 1/4" ply wood that but up to each the with holes cut out for the various hoses. Then it's all caulked. This was due to water getting g in while traveling.