Thanks all, didn't think of using bright lights at night, will try that, and moth balls.
I checked below my kitchen and bathroom sinks, and they were both sealed with a spray foam in the gaps by the previous owner, I know when I removed my queen bed platform I had two large holes that the wire bundles when through the floor for my converter/charger box. I filled those before building a new bed and storage. Only place I really haven't checked is under my shower pan, the access hole is tiny and I can't see much, but I do have a trap in my tanks storage compartment which hasn't caught a thing. I'd assume they would enter the coach that way if they were getting up through a plumbing hole.