Any alarm system, from a basic door alarm to one with remote monitoring - can be a good deterrent. Visual deterrents . Often, the stickers are enough of a deterrent to make thieves look for an easier target. Doors and locks . However, the locks are only as good as the door and frame in which they are installed.
Auxiliary locks can prevent sliding glass doors from being lifted out of their tracks.
Protect your valuables . Ask your local police about Operation Identification, and have your valuables engraved. Remove anything of extreme value from your home and store it somewhere safe.