I've not had mouse problems with my current camping rigs. But I was once outwitted by a mouse when I had my '72 Chevy camper van.
I knew I had been seeing evidence of mice in the camper but hadn't yet done anything about it.
One day I took the rig up to my local gas station/garage to fill up. As I was gassing up, I saw a mouse emerge from under the van right at my feet. It started out across the pavement, kinda looking everywhere for a place to hide.
I don't know what I was thinking but I started chasing it.
At first, it ran toward the line of bushes at the edge of the pavement. But that was pretty far away. So after a while it took a left and started making a big arc. I thought that seemed odd as the bushes were even further away in that direction.
But what it was actually doing was drawing me away from the camper.
Suddenly, it stopped circling and ran straight back toward the camper. I tried to intercept but, as I say, I had been outwitted. It easily got back to the camper before me and went under.
I caught a glimpse of it climbing up the inside of the right rear wheel.... on its way back into my camper.
I was stunned and looked toward the garage to see if anyone had seen that pea-brained mouse make a fool of me. Fortunately, no one had.... or at least won't admit to it.