The City Planning Commission may, by authorization, subject to the otherwise applicable zoning district regulations, allow on-site enclosed accessory off-street parking facilities with a maximum capacity of 15 spaces in existing buildings, provided that the Commission finds that:

(a)        the building does not have accessory off-street parking spaces;

(b)        such parking spaces are needed for and will be used exclusively by the occupants of the use to which they are accessory, except that car sharing vehicles may occupy accessory off-street parking spaces; however, the number of spaces so occupied shall not exceed five spaces or 20 percent of all such parking spaces, whichever is greater. For the purposes of this paragraph (b), such need shall exist where there are special circumstances and there are no reasonably viable alternatives to on-site enclosed parking spaces;

(c)        the parking spaces will not create or contribute to serious traffic congestion and will not unduly inhibit surface traffic;

(d)        the parking spaces will not adversely affect pedestrian movement;

(e)        the parking spaces will not be incompatible with, or adversely affect, adjacent uses including uses within the building; and

(f)        the curb cut accessing such parking spaces will not be inconsistent with the character of the existing streetscape.