(a)   A building containing one use shall provide the off-street parking spaces as required for the specific use.  A building, or group of buildings, containing two or more uses, operating normally during the same hours, and which have different off-street parking requirements, shall provide spaces for not less than the sum of the spaces required for each use, or the spaces required for a "large unit of development" of business buildings.
   (b)   Institutions, places of amusement or assembly  may assume that up to but not more than fifty percent (50%) of their requirements may be shared in adjacent parking areas which are accessory to business establishments, and which normally have different hours of operation.
   (c)   Provided, however, where there is a sharing of facilities by different owners, there shall be a contract covering a period of time as may be required by the Commission, and provided further that, should any of the uses be changed or the facilities discontinued, then the required spaces for the use or uses remaining shall be provided elsewhere as a condition precedent to the continued use of the building.
   (d)   Where private or public parking lots, or on-street parking are available and adequate within the walking distances, as limited herein, the Commission may modify the requirements set forth in Section 1149.05.
(1980 Code 151.86)