Mice in RV living quarters

We noticed one mouse turd on the counter a Couple days after winterizing and storing our 5vr a few years ago. We immediately cleaned everything. I then stuffed all the holes under the cabinets where pipes or wires came through with s/s scouring pads and spray foamed them in place. We have never had mice inside the living quarters since. But...they were getting in the walls and ceiling space. I had screened all the entrances to the cargo area with 1/4” wire mesh. But I missed one spot in the battery compartment. So now we have an $11,000.00 insurance claim on it. At the end of this season we are taking it in to a remediation shop where they will remove the roof and front panel and who knows what else to clean it.