Nothing in this Zoning Ordinance shall be deemed to require screening from the street side of the outdoor storage of new and used motor vehicles which are kept for resale to the general public by a licensed dealer. The screening of landscape plantings, or any new merchandise or products held for resale to the general public may be required, and such requirements shall be determined by the Department Director. If a property within a commercial zoning district is put to a residential use subsequent to the establishment of an outdoor storage area adjacent thereto, this section shall not apply.