Kyle Blackmon, the Esteys' apartment

In view of the strength of the luxury market, one couple is trying to more than double its money on an apartment at 15 Central Park West.

Arthur and Evelyne Estey, who bought a four-bedroom, 5.5-bath apartment in the building for $16.9 million in 2007, have put the unit on the market for $36 million, according to data from Streeteasy.com. The listing agent is Kyle Blackmon of Brown Harris Stevens, who also lives at 15 Central Park West, and who brokered the famed $88 million deal last year for Sanford Weill’s apartment in the same building. [more]