Very interesting, It has been my experience that you cannot seal a camper, trailer, etc from mice, it helps, but they will get in. The problem with poison is,,that a rotting mouse is about he most repulsive smell in the world, a single rotting mouse will drive you out I can not imagine what a couple would smell like. if you use poison, keep it outside!!!!! I like the bucket idea, I would have one outside and inside. as far as snakes go, I don't know anything about them but don't they only eat once a week or so? cats work, but if you are not around all the time that could be a problem, Good Luck
Doc