I know some people say it doesn't work- but I have had success with a product called "Freshcab" It is made in North Dakota and was developed for farmers to keep mice out of their tractors/combines/trucks. It has a lot of peppermint oil in it also- smells good to humans but mice hate it. Instead of killing them with poison and then dealing with the smell of their bodies this product just makes them leave. You do, however, need to replace the packets every 3-4 months. I don't sell the stuff- am not affiliated in any way- but it has worked for me.