I take a sticky trap with a dab of peanut butter on it
I also keep a small piece of 2x4 cedar from the kid's swingset in the car, best deterrent I have ever come across.
The key is to sand it once a year to keep it smelling, for some reason they hate it.
I now have a 4 gallon bucket swimming pool with 1" aluminum dowel, and Peanut butter on two pop rivets opposed in the middle, and cheese stuck on the ends and PB on the cheese.. so I can catch multiples of the suckers..
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I am going to put a whole TREE WORTH of Cedar in all of my vehicles.. Ive played with dryer sheets, and moth balls, and not been too satisfied with the results or the smell..