Go whole hog. As Pinhead says, electric fence and pee (the latter
particularly effective with rodents), but also fencing under the fence
because that is the way rabbits and woodchucks prefer. The electric
fence, strung a few inches from the top of the fence, is particularly
impressive, one touch and squirrels and deer stay away for years. I had
it down for three years, but I had a deer come in so I put it on again.
One month later, the breakins are over and the fence is off again. It
only cost 20 bucks. They have to get around the fence, either under or
over, so electric plus underground fencing take away both options.