I had a packrat building a nest under the starter battery box. Opened the hood, placed a work light. Power washed the engine compartment, spread a smelly granule product from the hardware store in the compartment, all around the ground. The only thing that worked was to leave, drove 500 miles in the summer heat. That did it.
Had mice in the underbelly of the fifth wheel, parked in an RV park. Removed everything that could be used as nesting material, tarps, plastic bags, cardboard boxes, all soft goods, and stored everything in hard plastic bins. Took down the divider wall, thoroughly cleaned surfaces with bleach water. Ran a rope light all around the perimeter outside on a day/night timer. They kept coming back. Found a product online that was steel wool embedded with tiny shards of stainless steel and stuffed it in every single possible entry point, every crack and crevice, around the slide out mechanism, the bumper rod attachments, battery box and I do mean every single possible point , no matter how small. That worked.
As for traps, I used a glue trap once and will never do it again. It doesn't kill, it torchers. The mouse was still alive eight hours after being caught and it had struggled so hard to escape, its belly was ripped open and guts were hanging out and it was still alive. I smashed it with a big rock.
Mice learn how to trip standard traps and get the bait. The only trap I use now that consistently works is this one:
https://www.fleetfarm.com/detail/vi..._source=bing&utm_medium=cpc&utm_campaign=Bing - 01 - Shopping - Farm %26 Livestock - US&utm_term=4581390076711127&utm_content=Pest Control
The best bait I have found is cat food kibble. Mice like grains, not peanut butter or cheese or bacon or any of that. I use the above traps with a piece of kibble as bait. It consistently catches and kills. I live in the country, there are plenty of mice and this works.
Good luck and happy hunting.
