Okay, you need some serious answers, training takes too long for a big bowser of a pup!
1) can you afford some chicken wire? It is cross-threaded fencing, very thin, and would do the job nicely. It may not be very aesthetic, but for the dog's purpose he will see it and treat it as a high fence.
2) the invisible perimeter electronic fence? your dog gets a little electronic zap through his collar if he goes over the boundary line (a foot your side of the fence) - after a week he would stay away from the fence.
3) line your fence with cayenne pepper, again a foot inside your fence line
4) get a dog run line - it's like a clothes line, has a trolley-like attachment that makes for easy running for your dog - attach the line at your house and end it at the furthest point from there (needs to be a pole or something at least 8 feet high)
5) this will take one day - keep walking him to the fence, not on a leash but holding his collar. About 1 foot before the fence, make him stop and sit, give him a treat, rub his head and belly, and give him lots of love and affection (overdo it!) - then walk him back to the door, make him sit, give treat and overdone loving. Repeat 50 times over a day. The next day, cut out the cookies, the next day slow down a bit on the affection, and so on... cheap, easy and quick!
I've trained pit bulls, golden retrievers and beagles.