Every unit shall have associated with it a minimum yard requirement around the perimeter of the unit and attached accessory structures of three (3) feet, except for those decks attached to the front of the dwellings situated in Block 100, Lots 26.01-26.76 and Block 69, Lots 15.01-15.28, which may extend to locations equivalent to those which existed prior to elevation or reconstruction as determined by prior property surveys conducted by a licensed surveyor. For those properties situated in Block 100, Lots 26.01-26.76 and Block 69, Lots 15.01-15.28 that do not have prior property surveys available, any new decks attached to the front of the dwelling can extend to a location which is the equivalent of the location of the front decks located on adjacent properties situated in Block 100, Lots 26.01-26.76 and Block 69, Lots 15.01-15.28. Structures shall be located no closer together than the sum of the yard requirements, that is, six (6) feet. Detached accessory structures are prohibited in the minimum required yard area.