Thanks for the replies everyone. We live in the country with farms around and the agricultural fences are economical and not bad looking especially with the black vinyl coating and I never really heard if basenji owners had any success with this type of fence. If it was totally up to me, I'd build fortress walls but that's not gonna happen.
Chris Battistelli
Personally I think it depends on your dog's personality. I live in an urban setting and had a normal chain link 4-1/2 foot fence – none of my dogs were jumpers and none has ever tried to jump it -- so this has worked well for me.
I did put up a 8 foot wooden fence around one corner because of nasty neighbor dogs but mine would simply try digging underneath and when I put rocks down they simply began to chew on the wood to make a hole, especially after a windstorm that toppled it and the wood splintered a little.
I do use a taller deer fence in the winter to keep the dogs out from one side of the house (neighbor's snow gets blown over into my yard there and builds up high enough for the dogs to walk out otherwise). It works well but is not the strongest gauge. After chasing rabbits into it, it becomes weak in spots and I have to do some patching. So if you use this style, then use the strongest gauge you can afford.
we have a 5' wooden fennce that has worrked great for about 10 years, but some of the posts have rotted & needed replacing. If I had to do it again I would get a colored vinyl fence.
A dedicated escaper is a challenge, but our 4 ft chain link has worked well for 30 years. I do like the kind of fence you are describing and will likely replace our aging, rusting chain link with 'farm fence'.
we have a 12 ft wooden fence 
But - my inlaws have an acre and have just fenced with your typical dog wire fencing. My two dont seem fussed by this at all and respect it.
We put up a 6" chain link last summer, August 2010, because Bitty had never shown any interest in climbing, but when we adopted Mr Baroo we were a bit concerned as he is a very active male , about 1-2y. So far the 2 of them have been quite satisfied staying in the yard, just over a half acre with pleanty of trees and shrubs for them to search for wildlife, so far the 2 of them have done away with one large buck cottontail and a male possom. Mr Baroo thinks he is the worlds greatest hunter. As long as we get the animals coming into our yard we assume that the B's will not try to go out exploring.
I know people with 4 ft fencing, and I know people with 4 ft fencing who have had dogs escape/never found/found dead. I wouldn't consider it for either a foster or home I'd place with unless the person backed it up with an invisible fencing about 3 ft in. Again, not a risk I want to take as I know my guys can go over 3 ft without any running start.
Polypropylene plastic fencing is nearly invisible.
http://www.dogsdeservebetter.com/cantfencemein.html
Another alternative for extended periods outside is the Friendly Fence. This is a fence that was originally designed to keep deer out and is constructed from high-strength and UV light resistant polypropylene plastic. The makers of this fence say it is “all but invisible to the human eye from as close as 15-20 feet away”. The fence comes in rolls of material that is secured to posts or trees by using zip ties. Ground stakes ensure that your dog can not push under the fence. Owners of aggressive dogs can use a nylon tension cable to reinforce the fence and there is a version that is 65% stronger than the standard fencing. The fence comes in heights from 5 – 7 feet. There is also a chew guard that can be attached to the bottom of the fence. The approximate cost of a Friendly Fence is between $159 - $345 depending on the size of your dog and the area you want to enclose. For more information on Friendly Fences you can go to their web site at www.friendlyfence.com. You also could use chicken wire between posts for a similar alternative.
I have concrete fence.. hahaha about 3 mts.. or 9 feet and 10 inches.
I have a 8 foot cedar fence. My female has dug out from under it numerous times. I've had to do some reinforcing. Dig down deep in front of the fence, bury bricks, staple field fencing to the bottom of the cedar fence and cover it all back up.
I have a section of rolling gate that is only 4 feet. My BRAT rescue, who's only 19 lbs, could totally jump over it if he wanted to but he hasn't. I worried about it at first but it's been 2 1/2 years and if he was going to flee, he'd have done it by now. Now that he's sleeping under the covers, I really don't think he's going to go anywhere!!!!
My current boy is a climber. None of my previous Basenjis have been. My dog run fence is only 4 feet, but two things deter him from climbing…...one is that the fence is not chain link and not tight.....it wobbles when he climbs on it, which is disconcerting to him. Another is that I took his breeder's advice (she has chain link) and tied PVC pipe on the top. If he gets that far he hasn't been able to get over the smooth pipe. The gate is the weak point, and he could get over that, but since it is in a corner I can put a plank across that deters him. As it turns out, I seldom use the dog run for him so it is a non issue, but if I wanted to be sure I would back it up with invisible fence to keep him off of it. I have had diggers, but none that dug with intent.......they were happy to dig a den in the middle of the run......however, I have cedar poles lining the bottom of the fence, which would likely help if they were to attempt it. Invisible fence will stop this activity as well.....
Chris, how about a compromise? Create a pleasant but smallish "Fort Knox" enclosure where the dogs can be outside without super close supervision ('tho I'm not a fan of B's being outside at all if their owners aren't home) Then go ahead and fence the rest in an affordable, climb-proof material for those times that you're able to keep a close eye on them. This approach works for some folks, depending on the size of the property and wildlife present, and how committed they are to keeping their dogs safe.
Keep in mind, 'tho, the fence isn't just for the dogs–depending on your property, you might want to securely fence a yard so you can enjoy yourselves on summer evenings without a skunk, racoon or bear sneaking up on you
