what do you use for mice?

CDepp

I would just introduce a natural predator to the environment or a smelling substance that repels them from the area. Call an exterminator, they will (should) have a line of effective products and use them around the location they are using to enter your storage.

The bucket seems like a good idea, yet the smell will probably attract them and you'll be left with always having to use it; same with any traps that attract the rodents.

Whatever your solution, I hope it works and best of luck avoiding any varmint damage!

Experience: grew up in rural Illinois in cornfield-country. '67GTO, 2 4wheelers, 3 motorcycles, and several expensive field tractors sitting in barn with possums, field mice, groundhogs, moles, etc. After a lot of $ spent in repairs and different trap-solutions that seems to intensify the number of pests, 3 cats ended up solving the problem.