However, individual leases can be more expensive than joint leases, since you'll be responsible for the entire rent payment. Individual leasing means peace of mind for you.An individual lease is a type of rental agreement where each tenant is only responsible for their portion of the rent. Easily add a tenant to an existing lease with our expert tips and stepbystep guidance. Simplify the process today. A lease is any oral or written agreement, express or implied, that creates a landlordtenant relationship, including any sublease and any further sublease. Everyone is both jointly and severally liable. A lease for a term of 1 year or less is valid whether it is written or oral. Many tenants who sign a lease for their apartment or rental unit plan to stay for the full amount of time required in the lease, such as one year. A joint lease is one in which all roommates in a particular apartment sign the same lease.