Invisible Dog Fence
"We put in Canine Fence 2 years ago and it has worked great. However please be aware that these systems have to have a complete circle (i.e. a single circuit that runs out from your garage and an electric outlet, around a perimeter (typically all around the house) and then back in again at the same point in the garage. If you just want to do a certain area of flower beds this may not work for you!
Approx cost for us (on a 1/2 acre property) was $1500.00 in 2009."