This guide will walk you through the paperwork for selling a house without a Realtor and various other steps that can give you a leg up. The offer to purchase real estate form comes in various forms in New York, and can vary based on the brokerage firm.NAR provides resources for working with FSBOs, including a brochure you can purchase from the REALTOR® Store. FSBO sales are not an easy process. " If you mean who actually writes the contract, the answer is Lawyers. Here's what to know about the paperwork for selling a house without a Realtor and more.