It shall be unlawful and a violation of this chapter for any owner to permit any tenant or other person to take up residence by a rental occupancy in any dwelling unit without the owner first having completed and filed with the Code Enforcement Officer a rental registration form approved by the Superintendent of Buildings. A new form must be filed whenever a dwelling unit or portion thereof has become vacant and the owner intends to permit a new tenant or other person to take up residence. A new form must also be filed whenever a transfer in ownership of a building that contains rental dwelling units occurs.