Under the SF Muni Code Section 37.2(r)(1), the definition of a "rental unit" does not include: "Housing accommodations in hotels, motels, inns, tourist homes, rooming and boarding houses, provided that at such time as an accommodation has been occupied by a tenant for thirty-two (32) continuous days or more, such accommodation shall become a rental unit."
Consequently, a short-term lease of less than 32 days is enforceable. If the property is leased for 32 days or more, then the unit becomes subject to the rent subsidization ordinance (RSO), and absent some other exception to the RSO (e.g., units for which a certificate of occupancy was first issued after June 13, 1979) , the occupant cannot be evicted except for "good cause," as defined in RSO Section 37.9.
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