All of those options are workable but nothing replaces mother nature. Get a cat or 2 and make them a home in your shed or garage (where equipment is kept). One month later you will not see any mice or rodents. They also like to eat bugs or anything small that moves.I use the stinkiest dryer sheets I can find. I use them in my camper, snowmobiles and anything that sits for longer than a month at a time.
Others use moth balls, but I can't stand the smell....and dryer sheets are easy to remove from the mufflers and sit right flat in my air cleaners.