Are home security systems worth the money?

The small, rectangular ceramic flower pots I kept in the two window sills of my bathroom had never budged an inch in the 14 years I owned the home, but one day I saw that one was close to falling out onto the counter below. I wondered if a small earthquake had caused it to move as I pushed it back in place. About a week later, I came home to find that the pot had actually fallen completely off the little ledge and onto the counter. This time I stopped to understand why, and I discovered that the small window was separated from the sill. I went outside. From there I could tell that the window had been pried from the house and someone had left a hacksaw on the ground. Evidently, I surprised whoever was trying to make their way into my home.

That day marked the end of my being blissfully unaware of the fact that there were people who were willing to commit crimes in my neighborhood. At the time, I was a single mom with a nine-year-old, and I felt a profound sense of terror. I locked the side gate and alerted my neighbors. The police couldn't lift any fingerprints, so nothing ever came of the incident except how it affected me. It wasn't long before I was interviewing home security companies.

I loved the system I chose. I could open the garage door and unlock the house from my key fob as I arrived home; I could even turn on the lights remotely or program them to come on automatically. If there was an intruder, a piercing alarm sounded and the security company would immediately notify police or the fire department if it was the smoke alarm.

Here's how the costs broke down for the system I got back in 1999:

• $600 — Door and window sensors, motion sensors, lighting timers, key fobs, alarm, security panel, and garden signs
• $200 — Installation
• $99 — Monthly service fee

Over the next eight years, I spent a little more than $10,000 for the convenience of security. I never second-guessed my decision because I needed to know that my son and I were as safe as possible after that event, and it made me feel like our home wouldn't be easily invaded while we were away. To this day, security is at the top of my list of priorities whenever I move. But now that my situation has changed and I'm not a single mom anymore, I'm more inclined to rethink my decisions about security. Like Kristin, my husband and I have been thinking of moving to a different apartment in the same city. We're not expecting that there will be an issue with security, but we are starting to travel more frequently and it would be nice to know our things are safe.

I haven't looked into a new system yet, but I understand that the equipment and installation is roughly the same (depending on what you want, of course). And the monitoring can run $15 to $100 a month, I'm told. Then again, the systems available today are much more sophisticated and, because my husband is well-versed in tech-y stuff, I bet he would love to put in sensors and monitor things over the Internet himself. I understand you can even monitor the temperature to save on utilities. But what is your experience? How do you keep your living situation secure, and how much does it cost? Is a home security system worth the money in your experience, or do you set up your own system and monitor it yourself?