I rent, so my options are limited as to surveillance equipment and alarm systems.
I compromise by living on the second story of a duplex. Two locked doors, one outside at the base of a staircase, one at the top that lets into the apartment proper. The latter of which is equipped with one of those stick-on, battery powered magnetic alarms.
Cell phone, pistol, and flashlight in/on the nightstand in the front bedroom where we sleep.
Retreat point is the rear bedroom that has no bed, but houses all of my other guns and ammo. Also here is one of those rope-ladder type fire escapes.
"The best diplomat I know is a fully charged phaser bank" - Montgomery Scott