The process of completing the purchase can seem somewhat daunting to many as it generally involves entering into a "contractual" relationship. California yacht brokers (and salespersons) can provide the expertise and experience needed to assist you with all aspects of purchasing a used boat.This form below is designed for use on upon the sale of a boat or vessel. Such a bill of sale is needed to confirm a party's ownership in the boat. A boat purchase agreement is a legally binding contract between two parties that establishes the terms and conditions governing the sale and purchase of a boat. Boats are taxable and subject to annual appraisal. I'm looking for an agreement between private parties instead of the Broker's agreements that can be edited to fit the situation. Survey SELLER and BROKER recommend that the BUYER have the. VESSEL surveyed as to the value and condition.