Re: Garage Security Systems
My 84 year old neighbor has a chain-link fence around her place, 5 foot high on the sides, 4 foot high in the front. Is it inprepetrable? No. she dropped her key on the wrong side of the fence and jumped over it. Is she likely to get robbed? I'm betting not, as the common house theif is going to go to the next house down. Same with a sign saying "Cameras in use". Are they going to risk it, or just go to the next house? Maybe the dummy camera is out in plain site, where the real ones are hidden. Motion lights are useless when you are at work during the day, but a camera by the front door makes that thief posing as a "door-to-door salesman" think twice.
One neighbor had his truck stolen on Groundhog Day (I blame Phil). Which was dumber, leaving your keys in the truck and having it stolen, or emailing all of your neighbors and admitting that you left your keys in your truck and it was stolen. It was recovered near the local university, where it had been left at a 24/7 gym with a large parking lot.
As pointed out, if they want in, you can't stop them. You just want to make it hard for the average amateur to get in.