Chelsea Enclave at 177 Ninth Avenue is one of many New York City sites that once housed a church and is now occupied by condos. Closings in the 53-unit building, which was constructed in 2008, started in 2010, and already one of the impressive penthouse has been put back on the market. The 3,454-square-foot duplex (which also includes 2,640 square feet of wraparound terraces) that is Penthouse A was actually purchased in 2011 for $9.5 million by an LLC. Now it's back, asking $16 million. It looks glassy and cold, but elegant. So, basically, it's a real penthouse.