Great idea. One thing to note is that some cars don't like OBD dongles which continually draw power after the vehicle shuts down. My BMW i3 sounds its alarm be

Great idea. One thing to note is that some cars don't like OBD dongles which continually draw power after the vehicle shuts down. My BMW i3 sounds its alarm because it assumes that an OBD connected when the car is locked belongs to a thief. So, worth finding someone with the same model car as you to ensure compatibility.