The 25-unit condo conversion of the former Children's Aid Society building at 215 Sullivan Street is nearly sold outafter just three months on the marketso what better time to create a model unit? Reps sent over the first images of the 3,254-square-foot, 4BR/4.5BA unit, giving a first look inside the historic Calvert Vaux building that holds the converted spaces (there's also a newly-built part). It's located on the third floor of the Vaux building, and it was outfitted by the project's interior designer, Eric Cohler. This exact unit has actually sold, but an identical home on the floor above, 4A is currently listed for $9.6 million. In addition to that one, three others are available: two townhouse units, which have private entrances and garages, and 5D, located in the new construction.