You must insist that the crash be reported to law enforcement so that a law enforcement officer can complete the appropriate forms. You shouldn’t try to negotiate a payment agreement with the other party to settle damages. Other suggestions include:
Make sure the investigating officer records complete insurance information for all parties on the crash report. Report the accident to your insurance company immediately. If the other party is insured or uninsured, be sure to report that information to your insurance company so that they can pursue compensation since they have more information resources at their disposal.