What paperwork should I keep after buying a car?

Keep the signed sales contract or retail installment contract, buyer's order, bill of sale, Buyers Guide for used cars, any warranty or service contract documents, add-on product contracts, temporary tag paperwork, title or lien documents, registration and insurance proof. Also keep the window sticker, inspection results and service records. Store copies digitally. You will need many of these to resolve problems, cancel optional products for a refund, or sell the car later.