One thing that we have used for years with great success is Bounce Fabric Softener sheets. We just wrinkle them and spread around the interior of the coach, cabinets and in the storage compartments.
We change the sheets when they start to loose their odor.
In ten years that we have been using them in the RV's, we had one mouse get in and it was during a time when we hadn't changed the sheets and they had lost there smell.
We were told that the mouse hate the odor of the Bounce sheets and we were told that the sheets mask the odors of food and other things so the mice do not get in. Either way it seems to work.
Added bonus is that the RV always smells fresh.
Ron