Choose a controller with back up battery so the system will stay active in the event of a power outage or if the Internet is down. If you will be installing smoke alarms you’ll need the extra power of a 24 hour battery back up, not the 4 hour back up offered by many manufacturers. THE COST FOR SECURITY There are two costs to keep in mind when shopping for a home security system. The first is for the equipment and the installation, if you’re having it done by a professional. It can run from a few hundred dollars for a basic installation or less that half of that if you install it yourself to north of $1000 for a full feature system with specialized sensors and wireless smoke and CO detectors. The second is the monthly service charge that includes fees for software driven features and central station monitoring.