Neighbors or a service are the most popular ways of keeping an eye on things.
There are some tech items available that would allow you to monitor with sound and/or video inside the home, accessible by your home computer.
Gated communities sometimes give a false sense of security, and people are more likely to leave doors unlocked etc.... which makes them easier targets than your home with the doors locked.
Motion activated lights and interior lights on timers make it appear someone may be home. You just want to look less appealing, punks want easy targets.
All the Best,
Jim Sweat, ABR, CRS, GRI, CDPE, e-PRO, ILHM
Sandals Realty http://www.ExplainShortSales.com