An ADT sign just tells thieves to break in a window and stay out of main halls or living rooms. 90% of the ADT systems are only on the doors and 1 motion in the living room or hall. I know this because after the ADT customer gets broken into and their system doesn't do it's job, they call me. I have to tell them, that's what you get for buying a $99 alarm. Once they get out of that 3 year or 5 year, revolving contract, I put in a full system for them.