When we were still parking our cars outside we developed an issue with mice for (unmentioned reasons) LOL. I found these to be quite effective LINKY

But not sure if I would rely on them in your situation. The only other thing I found to work extremely well was Peppermint oil /extract. I would treat rags with it placed around the tires which is their normal path of attack. The scent is STRONG and lasts a month or more before needing to retreat. You can check AMZ for reviews and buy there as well as a local store.

I do have several of the Victor zappers, if interested PM me. I won't be surprised if you don't