If you are selling a used vehicle as a private citizen, you are legally required to give the buyer a Car-Pass unless the buyer is a professional vehicle dealer. What happens if you don't? If you don't, the sale is invalid and the buyer can request a full refund afterwards. Always ensure the buyer signs for his copy of the Car-Pass. The Car-Pass must be no older than two months. You will find the validity date at the top right of the document.