I've just sold my car and I'm uncertain as to at what point it will legally transfer to the new keeper. I have prepared a handwritten receipt that both buyer and seller signed at the time of transfer. The car is being driven to its new keeper untaxed. It will inevitably be spotted on some ANPR device in London or may even commit a parking offence. What precautions can I take to avert liability? Due to the long Bank Holiday weekend, I won't be able to get the logbook to the DVLA until late next week.