Moth balls also work wonders with rats.  And squirrels.  Have used them
with success to drive away both in the past.  You have to remember to
check and replenish them from time to time.  I had a friend who had
squirrels that had worked their way into the crawl space above her
nearly flat roof.  We put moth balls in the area and in about 6 hours,
never heard any more squirrels.  Then I patched the hole for her.

Haven't tried them in the house when I have mice there, because I don't
want to smell the things.  My useless, though lovable cats, come to the
2nd floor almost every night and sleep, leaving the mice free to play in
the kitchen.  So, I have to use traps when the mice appear.

But I would think moth balls would be great to protect the van.  Remove
them and head out on your trip, windows open - the breeze will pull away
the smell before you make camp.  If mice are around the campsite, just
put some on  paper plates under the van and that would probably
discourage them.

--
Sam Walters
Baltimore, MD

89 Syncro GL
85 Westy Weekender
84 Vanagon, original owner, soon to be retired, just too many problems

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