Wall Street titan lists bulletproof Upper East Side mansion for $80 million; property could become the neighbourhood’s priciest

John Mack and his wife Christy are putting their lavish Upper East Side townhouse on the market for a staggering $80 million. Selling at this price would establish a new benchmark for townhouses in New York City. Since purchasing it in 2009, they have extensively renovated the property, resulting in a 16,000-square-foot masterpiece that boasts upscale features such as a wellness club and exclusive guest quarters.