No modification, amendment, or alteration in the terms or conditions contained herein shall be effective unless contained in a written document prepared with. A wellwritten sales contract covers all elements of a transaction and includes remedies should the deal not go as planned.(b) The effective date of this Contract shall be the date when the last one of the Buyer and Seller has signed or initialed. Includes a detailed look at how to fill out every blank of the contract with the proper information and format. 2022. Make sure their terms are realistic if you don't want to buyers to have an easy out. Electronic signatures on bid documents will be accepted pursuant to Section. 668.004, Florida Statutes.