n today's tight housing market one way to make your income meet the rent is to have a roommate. While this can be an excellent way to find (and keep) affordable housing, here are some things you should know:

If you are the only person who has signed the lease, in addition to your immediate family, state law allows you to have one roommate (i.e. an occupant of the apartment who has not signed the lease). Your roommate's dependent children are also permitted. Any lease provisions disallowing a roommate (and dependent children) are illegal. If your lease originally had two or more tenants you may have an additional roommate or roommates provided that the total number of tenants and occupants (excluding occupant's dependant children) does not exceed the number of tenants on the original lease. For example, if three tenants signed the original lease and one moves out, you may have a roommate to replace the departed tenant.
If your apartment is rent stabilized, you may only charge your roommate(s) a "proportionate" share of your rent. A proportionate share is determined by dividing the legal regulated rent by the total number of tenants named on the lease and the total number of occupants in the apartment - not including the tenant's spouse, family members or the roommate's dependent children. For example, if you live with your spouse and two children and only your name is on the lease, and you have a roommate who has one child, only you and the roommate are recognized for the purpose of calculating a proportionate share of the rent. You may therefore charge the roommate up to 50% of the rent.
Check your roommate's background thoroughly. If you don't get along, and your roommate refuses to leave, you do have the right to evict your roommate. However, if the roommate refuses to leave, the ensuing eviction process could be both painful and expensive. Remember, until the eviction process is complete you may have to live with this person.
If you join someone as a roommate (i.e. your name isn't on the lease) another set of problems can crop up. In most instances, if your roommate (the leaseholder) leaves, you have no right to keep the apartment. The primary tenant might also decide to temporarily sublet to someone, in which case you will suddenly have a new housemate not of your choosing.