Food and a place to sleep is all mice really want.
Take away the food and the mice won't live there anymore.
What I am saying is after the season do a thorough cleaning in the fall wash all kitchen areas with a bleach kitchen spray available at most stores.
Vacuum the rugs thoroughly and that means THOROUGHLY.
Remember the potato chips crumbs that grand kids dropped on the rug may not be visible. But to a mouse it is food on a grand scale.
Mice will not sleep in your unit and dine in the neighbours, they really don't like the walk between units they sleep where they eat!!!!
What I am saying is cleanup and you will not have problems.
I realise that it is a different situation for full timers as food is always present but for seasonal RV's there is a solution.
I have read with amusement about better mouse traps but If you don't have mice you don't need traps.