In the case of private car sales, the buyer and the seller must appear together at PennDOT with photo ID and sign all documents in front of a PennDOT agent. Some people need a pink slip because they just moved to the state of Pennsylvania, while others need a certificate of title because they have purchased a used car from a friend or inherited a vehicle from a relative. Pennsylvanians who need a title for car ownership must file the appropriate application with PennDOT.