Keeping Mice Out of Camper

Your best chance to "help" --clean the whole place very thoroughly (vacuum & wash out cabinets, drawers, under furniture, under sinks, etc.); I'd also put all your eating utensils and cookware that are in drawers in heavy plastic containers or remove them entirely or you will have to wash everything come spring); also suggest you seal up your toilet bowl by taping a piece of wood or you'll have dead mice floating in there come spring; fill P-traps with pink antifreeze then close stopper in all sinks (mice will need fluid so these sources are a draw); set many traps and check often; put out dryer sheets everywhere (helps the place smell nice and for some folks will actually deter mice, but hasn't in our case, just smells better); we put out packages of "Fresh Cab" (bought at Menards, so far it helps but did not keep them out 100%); if you live in a humid region set out dehumidifying containers and change as needed (however since these containers will fill with fluid as they work...they too can draw mice); remove anything silicone or foam rubber (mice ate the frying pan handle covers off); store all cotton items elsewhere (mice used the cotton fringe off my throw rugs for nesting, that goes for paper items too); and of course if you can find any small holes mice can get in to...fill them with steel scrubbies or at least steel wool).