In an addendum to a lease, you will need to add the dates, names and addresses of all parties involved in the original lease agreement. Co-Signer and Rental Guarantee Agreement.Is a Lease required? This state-specific Lease is customizable and includes UT laws. A homeowner must provide a copy of the lease, together with the required addendum form, to the Association. A homeowner must provide a copy of the lease, together with the required addendum form, to the Association. Please keep in mind that while this is a sample lease contract, there may be an addendum or two that are specific to the home you lease. The first tip to creating the best lease agreement in Salt Lake City, Utah, is to have a customized template to provide an overall format. The Agreement Utah form serves as a comprehensive residential rental contract between a tenant and an owner for properties located within the state of Utah. B. First Addendum to Lease Agreement dated July 2, 2010. c.