21 East 37th Street

Most of New York City's grand and historic homes have been altered for modern-day use as apartments, libraries, hotels, diplomatic buildings and the like. And when it comes to those that have remained as opulent single- or multi-family homes, most have changed hands so many times that we don't know much about their history. That is not the case for this massive 9,300-square-foot townhouse across the street from the Morgan Library. The home was originally the residence of J.P. Morgan's attorney John Trevor, Sr. and is currently in use as a 10-unit apartment building–albeit a rather special one with some unique spaces like a private office and a gorgeous rear parlor with symphony-ready acoustics and 13-foot ceilings. Whoever purchases the home, on the market for $14 million, could create a vast five-story mansion (there's already an elevator), or any number of alternate configurations–but they'll still have great sound in that back parlor.
The neighborhood blows up, then the lawyers move in