Mix the peppermint oil with water and spray it. Rats, mice and squirrels are repelled by it. I had a wiring harness eaten out of a tractor and read about the peppermint oil repelling rodents. So now tractor, mower and truck have a nice peppermint smell and so far, no more lost wiring. Oh yeah, it repels many insects as well.
The following link tells how to use it. Although this is for mice, if you search on the internet you will find it also works for rats, squirrels, flies, and many other pests.
https://www.homesandgardens.com/advice/using-peppermint-oil-to-get-rid-of-mice