a retailer i spoke with came up with a decent solution, after meeting the customer and being happy they are genuine - use the company hack and go out together, they follow you = your route at your pace.
They have done this because I've been phoning them every day asking for mine to be sorned
The bastards
On a positive note paperwork needs to be watertight before any customer allowed out on a test drive even more so unacompanied
It wont happen here but I would be fitting gpr tracking cameras in any car I let out to confirm no nips etc
Maybe one for lawgistics to do a legal on