(1) Any development subject to the provisions of this Chapter shall also be subject to the following restrictions:
(a) The applicable portion of the development shall have recorded against it a Declaration of Covenants, Conditions and Restrictions requiring that the affordable housing units remain affordable for ten (10) years from the date of issuance of the certificate of occupancy, in the case of units for sale, and fifteen (15) years in the case of rental units. Such covenants shall be recorded by the developer with the Department of Records, shall run with the land for the entire ten (10) or fifteen (15) years, as applicable, and shall bind any owner of the affordable housing units and any other party with an interest in title to such units. In the case of units for sale, such covenants shall further require that, upon subsequent sale of such units after ten (10) years, the seller shall pay over to the City an amount equal to twenty percent (20%) of the increase in market value. Such increase shall be calculated by subtracting from the sale price (i) any increase in value due to improvements; and (ii) the original sale price when the unit was first sold by the developer. Such payments shall be appropriated and spent by the City in the same manner as any payments pursuant to subsection 7-104(1)(b), relating to Affordable Housing Fee.