Before finalizing the sale, ensure you have the vehicle title, bill of sale, and any required transfer forms ready. Be cautious of buyers who pressure you to skip these formalities, as they may not have your best interests in mind. Always ensure that the proper paperwork is completed to protect yourself legally. The environment is an increasingly important consideration when selling scrap cars. Many older vehicles contain hazardous materials such as oil, coolant, and lead-acid batteries, which must be disposed of properly.