[oh8eleven]

DOGS, a couple of big'uns, who BARKED when ANYONE came NEAR the house ...
Nah, pain in the arse - would keep everyone awake all night, including the neighbors, not to mention poop patrols, feeding, baths, etc.
Buy an alarm system, install it, forget it.

[cloudmountain]

Alarms are so often triggered by chance. They go off so often that often people ignore the alarm. Lol. Sorry for the "oftens."
I remember the FIASCO of car alarms. They became so annoying that people stopped putting them in.

Garages are best.