In the event that you are using one of these for a trailer or car things should happen pretty quick, likely before the thief knows an air tag is with it, or can find it if they do. Some friends of mine and I put air tags on our kids while we were at a crazy busy place. At one point we left the hotel and my son did not have his air tag with him, we had barely pulled away from our parking spot before it told me that I had left an item behind, so roughly 2-3 minutes from leaving the room to getting a notification that it wasn't with me. So if you set a trailers location you should receive an alert rather quickly that is has moved from its spot(unless you are with the item). I know if I am at work and I get an alert my trailer or car is moving I am going to make a phone call to the police pretty damn fast.
Being left behind is one thing since it breaks a connection with the phone designated as the owner. I'm not sure leaving a trailer somewhere would alert you as fast. I would have to guess it will need some type of way to connect to the internet to alert you. Possibly requires an apple device to alert you. So if an android person steals your trailer, you may be SOL.
