An apartment lease is a legally binding contract between a landlord or property owner and a tenant that outlines the rules agreed upon by both parties. It specifies the length of time the tenant will be renting the apartment and the amount of rent they will pay each month. A lease can be from one to many pages long and is a clear, specific, written record of the terms of living in the apartment. Both the landlord and the tenant benefit from a lease. It provides security to the landlord, ensuring a source of revenue each month and a locked-in rent rate for the tenant. A lease agreement offers stability for both the renter and the landlord, and once it is signed, the landlord cannot raise the rent, even if property or rent values rise. Most residential leases are standard with the same terms for all tenants, while leases for commercial properties are usually negotiated in accordance with the specific lessee. A lease can be a long-term contract, usually set for a minimum of one year, or a month-to-month lease that allows the tenant or landlord to terminate the lease at any time.