"As they're building a house, some people don't think about a security system," says Melissa Brinkman, Director of Business Development at Custom Alarm. "They plan to get one put in later, but the best time to start is when the house is being built."

The best time, in fact, is before the drywall gets installed, when access is easy and running wires practical. When the house is finished, the wiring will be ready for the security devices. But if your house is already sheetrocked, it can still have a security system, and a good one, because wireless technology works just as well as its hard-wired kin.

The advantage of a wire network is the lower cost of its devices. "You can also combine hard-wired and wireless equipment. They work well together," Brinkman says.