(A) In areas designated for hotel use, resort use, or transient vacation rentals, pursuant to county authority under section 46-4, or where the county, by its legislative process, designates hotel, transient vacation rental, or resort use; provided that, if a county with a population density between 100 and 1000 people per square mile establishes a time share zoning district that allows time share units and time share plans, such a county may then restrict time share units and time share plans in other zoning districts, including areas designated for hotel use, resort use, or transient vacation rentals;

(B) In a hotel where the county explicitly approves such use, in advance, as a nonconforming use; or

(C) In a county with a population in excess of five hundred thousand, in an existing hotel which is a valid nonconforming use under county ordinance; provided that the property shall have at least sixty units and at least forty per cent of the units, upon completion of sales of the time share intervals in the project, shall be made available for sale as residential apartments or rented as residential apartments."