Your landlord has a right to know the identity of people residing in his/her property. Moreover, it's quite possible that your written lease places restrictions on whom can live/reside at the premises. In addition, your written lease may have restrictions on whether you can sublet or otherwise allow other people to rent your apartment. Subleasing or allowing other individuals to stay without landlord approval could be a violation of your lease terms, and you could find yourself in breach of your lease.
Keep in mind, I haven't reviewed your lease. I'd suggesting having an attorney review it to ensure that you're not doing anything to put yourself in breach of its terms. That being said, your landlord absolutely can make him move depending on the terms of your written lease.
DISCLAIMER: Brandy A. Peeples is licensed to practice law in the State of Maryland. This answer is being provided for informational purposes only and the laws of your jurisdiction may differ. This answer based on general legal principles and is not intended for the purpose of providing specific legal advice or opinions. Under no circumstances does this answer constitute the establishment of an attorney-client relationship. For legal advice relating to your specific situation, I strongly urge you to consult with an attorney in your area. NO COMMUNICATIONS WITH ME ARE TO BE CONSTRUED AS ARISING FROM AN ATTORNEY-CLIENT RELATIONSHIP AND NO ATTORNEY-CLIENT RELATIONSHIP WILL BE ESTABLISHED WITH ME UNLESS I HAVE EXPRESSLY AGREED TO UNDERTAKE YOUR REPRESENTATION, WHICH INCLUDES THE EXECUTION OF A WRITTEN AGREEMENT OF RETAINER.
I agree with Ms. Peoples. But the landlord must have a good reason to reject him.
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In San Francisco, a landlord-tenant relationship is typically governed both by the written lease and any applicable rent control provisions. The San Francisco rent control ordinance sets forth certain limitations and rights with regard to subletting and/or introducing a tenant not originally on the lease (which I will cut and paste for you below). Your lease may provide greater leeway in permitting a roommate or subtenant than is required by the rent control ordinance, but generally not less. I would suggest that, depending on the relevant provisions of your lease, you address the landlord regarding the new tenant and try to work on something agreeable to both you and the landlord, if the landlord is reluctant to add the roommate due to his credit or lack of credit history. The landlord's concern is likely this: once the new tenant has moved in, even if YOU move out, the landlord cannot remove the roommate without following the same law that applies to you. The landlord may not be willing to take on the risk, i.e. potential cost of evicting the roommate, based on his credit or lack of rental history.
It is difficult to interpret a lease without reviewing the full agreement, but your lease likely contemplates and/or expressly prohibits the addition of a new tenant, and probably contains language the governs (or purports to govern) your situation. Here is what the rent control ordinance provides: "...(A) Provided that notwithstanding any lease provision to the contrary, a landlord shall not endeavor to recover possession of a rental unit as a result of subletting of the rental unit by the tenant if the landlord has unreasonably withheld the right to sublet following a written request by the tenant, so long as the tenant continues to reside in the rental unit and the sublet constitutes a one-for-one replacement of the departing tenant(s). If the landlord fails to respond to the tenant in writing within fourteen (14) days of receipt of the tenant's written request, the tenant's request shall be deemed approved by the landlord.
(B) Provided further that where a rental agreement or lease provision limits the number of occupants or limits or prohibits subletting or assignment, a landlord shall not endeavor to recover possession of a rental unit as a result of the addition to the unit of a tenant's child, parent, grandchild, grandparent, brother or sister, or the spouse or domestic partner (as defined in Administrative Code Sections 62.1 through 62.8) of such relatives, or as a result of the addition of the spouse or domestic partner of a tenant, so long as the maximum number of occupants stated in Section 37.9(a)(2)(B)(i) and (ii) is not exceeded, if the landlord has unreasonably refused a written request by the tenant to add such occupant(s) to the unit. If the landlord fails to respond to the tenant in writing within fourteen (14) days of receipt of the tenant's written request, the tenant's request shall be deemed approved by the landlord. A landlord's reasonable refusal of the tenant's written request may not be based on the proposed additional occupant's lack of creditworthiness, if that person will not be legally obligated to pay some or all of the rent to the landlord. A landlord's reasonable refusal of the tenant's written request may be based on, but is not limited to, the ground that the total number of occupants in a unit exceeds (or with the proposed additional occupant(s) would exceed) the lesser of (i) or (ii): (i) Two persons in a studio unit, three persons in a one-bedroom unit, four persons in a two-bedroom unit, six persons in a three-bedroom unit, or eight persons in a four-bedroom unit; or,
(ii) The maximum number permitted in the unit under state law and/or other local codes such as the Building, Fire, Housing and Planning Codes; ... ."
Depending on the terms of your lease, you should be able to add a reasonable roommate to your tenancy. If your unit is covered under the SF Rent Ordinance (generally, an apartment building built prior to 1979), then your landlord cannot unreasonably withheld consent to the sublet following a written request from you. The "reasonableness" of a potential roommate should be determined by his credit, income and references.
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