We have permanent fence on two sides, and put up a fence every year around the other two sides. I use the middlebuster to dig a groove and place the fence in the groove...this puts the fence several inches below "ground level".
I'm shocked no one came up with my solution. Get a cat. I've never had an issue with the rabbits in my garden. I only have the problem of what sounds like a baby crying when the cats are attacking the rabbits.
I've found the foxes like my chickens more than the rabbits.