The best mice repellant I have seen is Irish Spring soap. They cant stand it. I cut it in about an inch and a half squares and put it where my plumbing and electrical comes in my RV. I put in the cabinets, storage, etc. My RV has been parked at Toledo Bend for almost 5 years. No sign of the first mouse. I keep food in it year round. I believe it it keeps the wood roaches away also. We are surrounded by the Sabine National Forest, so there are plenty of critters. We have not had the first snake pay us a visit either. I put out fresh soap every 3 months or so. It works.

