When a second brownstone became available next door to Michael Feinstein’s Upper East Side residence in 2005, the singer purchased the four-story home, which he connected with his original structure to create an 8,000-square-foot residence. “We realized the only way to find what we were looking for was to create it ourselves — it’s an extraordinary feat of engineering,” Feinstein tells THR. The home, with it’s double-sized back garden, is on the market for $17.9 million.