New answers tagged garage-door
I see several solutions: You could install a security camera; Use a garage door sensor, for example Asante Garage Door Opener which notifies you by mail, SMS or mobile app; or use a smart home solution, see the review by CNET.
Unless that is built into the opener, you will have to buy or build something. What that something is will depend on your needs and how fancy you want to make it, but it's essentially the same problem as putting an alarm on that door.
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