I absolutely swear by the bug granules you can buy at HD or Lowes that you sprinkle around the border of the camper, particularly where the tires and jack meet the ground. Since it's easy enough to do it I throw a bit under the camper as well. Mine lives on a site so it's worth the nominal expense. In 3 years I haven't done anything else except ant traps once and it was my fault because the counters didn't get wiped down well enough. Also, if you're only camping for the weekend that's barely enough time for the treatment to work a whole lot, in fact it just gets them on the move to get away from the treatment.