Under California law, a manager, janitor, housekeeper, or other responsible person must reside at a rental complex in which there are 16 or more apartment units (California Code of Regulations Title 25, Section 42). Only one responsible person is required for all structures under one ownership and on one contiguous parcel of land. If the owner does not reside upon the premises of any apartment in which there are more than four but less than 16 apartments, a notice stating his or her name and address, or the name and address of his or her agent in charge of the apartments, must be posed in a conspicuous place on the premises.