Door alarm options?
I make service calls and yesterday I was at a house that has infrared sensors guarding the exterior area of doors, driveway, and porch entrys, etc. It sets off an alarm inside the master bedroom, volume adjustable, and indicates which sensor has been activated. It needs to be adjusted for height so that small animals don't set it off, but it was reasonably priced, no subscription needed, just batteries. It has it's pros and cons, but I'm going to learn more about them. They can be hidden or left well exposed, so that a potential burglar would see them, or some of them. It reminded me of a "cat and mouse" dynamic. The guy was retired military, was in the "sand box", as well as many other places. Don't know where he got them, but I'm sure a google search will help, as will our fellow diy'ers, I trust.