Fence me in

Time to get serious again. To get a dog, we need a fence. One, because I like the idea of sending the dog out the backdoor to do his business without having to put shoes on. Two, because we are too close to the busy road for me to really be comfortable letting him free range. Three, because I hope in my silly little head that while it won't prevent deer from getting in, it may 'encourage' them to just eat the things on the side they're already on instead. (ok, so that has nothing to do with dogs) and Four, because if we end up talking to a rescue instead of just the pound, they all say we need a fence. Which brings us to the question of 'how high'? Obviously, the answer to this question is 'just a little higher than the dog cares to jump'. Which is hard to answer when you don't have a dog yet. So the better answer is 'as high as the rescue people say it needs to be'. Except that question leads you back to either the first, unhelpful, answer or 'over six feet'.* Which is nuts. I have seen a seven foot fences two places. The first is itty-bitty inner city lots where you don't want to see into your neighbor's yard, or the busy street. That makes sense. You want to keep the outside out as much as possible, and the yards are better measured in square feet than acres. The only place I have seen that tall of a fence surrounding something as big as what we are fencing is a bonafide prison. That is not happening. Because it would look like a prison and cost (I'm estimating here) one million dollars. ** So, right now we're nittering back and forth around five feet. We want the wire to go down to the bottom, so it's not overly tempting to squeeze/dig underneath. Would it look stupid for the wire to be higher than the top rail? Since the wire comes in even feet, and the rails are six inches, if the wire hits the bottom of the rail, the fence will be something and a half feet tall. Is four and a half too short? Is five and a half overkill? If we go with five and a half, we have to get the six foot posts... how much do those cost? It's terribly frustrating to be having to make these decisions based on a random imagining of how high an imagined dog might like to jump. Particularly when the contractors seem fairly convinced that a four foot fence is the best size ever, and doing something else is just plain weird. *** * Another place it might go is 'that's hard to answer before you know what rescue you're using, which is hard to know before you know which one has the dog you want, which is hard to find out before you get started on the fence that will take a long time to build, in which time the dog you want may not be there anymore' yeah, that one was helpful. ** But seriously, fences are fraggin expensive. We're looking at close to 10k for a not-seven-foot-tall one. *** And that's after they've stopped laughing at you for not wanting to let your dog run loose to begin with.