Why sell used cars when you can get in on the building boom that has been creeping down the slope of The Slope? Rather than sell the property they’ve held for the past four decades, the owners of the lot at the corner of 3rd Avenue and President Street have decided to develop it themselves. Unfortunately, their first attempt to get the Department of Buildings to sign off on a 18,000-square-foot hotel met was rejected three weeks ago so we can only assume they’ve gone back to the drawing board. GMAP P*Shark DOB