I had a 'spare' smart phone after my wife passed away, so I hooked it up to a power source and locked it in a spare cupboard.
I turn it on before I head away and leave it turned on.
It is on an ALDIMobile 12month very low cost plan as I don't use it for data or calls.
If someone pinches the van, I can do a 'where's my phone' search to find the phone, and therefore the van.
It is an easy option if you have a spare phone kicking around.

glids