New Trailer and Off-Highway Vehicle (OHV) Report of Sale. California Bill of Sale Forms (3).A California bill of sale is an official document used to record the sale of personal property between a buyer and seller. The Trailer is to be sold free and clear of any liens, encumbrances, or mortgages. The California bill of sale form helps individuals document data on a transaction involving the sale, trade, or gift of personal property. A quick video on how to correctly fill out the California DMV (Department of Motor Vehicle) Bill of Sale form. You need a California Trailer Bill of Sale form to register your trailer with the DMV after purchasing it from a private party. Demand that they sign a valid Bill of Sale. Include crucial details such as the sale date, buyer and seller information, trailer description, VIN, sale price, and any included warranties. Please fill out the form below.