A lease renewal agreement contains the length of the renewal period and any modifications to the original lease, as Rocket Lawyer indicates. Any such changes need to be acceptable to both landlord and tenant and should comply with local laws.
Both parties may use the lease renewal agreement as a negotiating ground for rent increases, changing units or improvements to the property advises The Huffington Post. A landlord may propose a rent increase knowing that after a year, the costs of moving may be prohibitive. Before agreeing to a rent increase, a tenant should investigate local laws to ensure it is legal and reasonable for the area. If it is legal, a tenant may still negotiate for a better deal. Unless obligated by the original lease, neither party needs to sign a renewal agreement; in such an event, any end-of-term provisions from the original lease or local law then apply, as noted by FindLaw.