Most of us store lawn-mower gas in the garage, so be prepared for a fire. Get a 5- to 10-pound U.L.–listed extinguisher and mount it in an easy-to-access spot. It should carry an ABC rating, certifying that it's effective against wood, oil, and electrical fires. Though we're sure you know to open the garage door when your car's engine is running (right?), installing a carbon monoxide detector will give you added peace of mind. And while you're at it, check your garage-door opener to make sure it has a U.L.–listed motor and an auto-stop feature that will prevent the door from closing in case a child or pet tries to sneak underneath.