I want it up high so no one can easily get to it to trash it. It has to have power, which we can run into the eaves of the barn so a fence post won't really work anyway. I dare anyone to try to access the barn through the roll up door when we're home, which is pretty much 24/7 and at night, there is the baby monitor in the barn that will telegraph their activity. That thing is so blasted noisy. The human entry door could be lock-picked so that is where I want to focus. When my chickens groups are fewer and I can corral them into fewer pens, I will divide the barn into chickens in front and storage in the back half of the barn where the roll up door is so even without chickens, I need security.
I could possibly put it on the back of that old coop that is nearest the barn pointed toward the barn, though. Hmm, that's a thought. It would show the entire front of the barn and a good portion of the pen that way and that building has power as well.
Sounds like the security system you have is really nice. I have placed a padlock on my coop-you never know about people.