How to alert garage door opening after hours
I help out at a children's camp. They've had two generators stolen from the garage. I have one camera looking at the parking lot and plan to put another looking at the two garage doors. But a) they're coming in from the woods avoiding the parking lot and b) if they're not completely stupid, they're probably using masks to hide their identity.
What items should we install to alert us of after hours usage to somehow Open the garage doors (there are two they could access). And probably an audible alarm and a notification to the admins.