Treat any door to your garage like an external door, which means making sure it has a good dead bolt on it. Burglars will scour neighborhoods with common brands of remote openers, looking for garage doors that will open. Change your garage-door opener code. New openers come with factory-set codes that are meant to be changed, but many people neglect to do so. Keep your car locked with the alarm on, even in your garage, and consider additional anti-theft devices such as The Club or any device that allows you to track your vehicle through a GPS system. Use a large key lockbox in the garage for storing rarely used car keys. Make sure garage lights can be turned on from inside the house so you never have to walk into a dark garage.