Robert Hurst, former president of the Whitney Museum of American Art, 950 Fifth Avenue, unit 89

The limestone prewar co-op at 950 Fifth Avenue has only seven units and a reputation as a haven for billionaire bachelors — reportedly single Boston Properties CEO Mort Zuckerman lives there, and bigwigs Dennis Kozlowski, formerly of Tyco, and Jonathan Tisch of Loews Hotel are ex-residents. For a cool $29 million, one newcomer could join the pack. The 12-room duplex that belongs to Robert Hurst, a Goldman Sachs alum and former president of the Whitney Museum of American Art, hit the market today, according to Streeteasy.com. The spread, unit 89, has views of Central Park, a maid’s room and on the second floor, via a limestone staircase, three bedrooms. Hurst, now a managing director at private equity firm Crestview Partners, could not be reached for comment and Brown Harris Stevens’ Alexis Bodenheimer, who is the exclusive agent with the brokerage’s Cathy Franklin, was mum on the listing. TRD [more]

Mark Madoff and the Nantucket house at 51 Wanoma Way

The beach house in Montauk found a buyer quickly, and for more than its list price. Now, as the investigation into the fraud run by Bernard Madoff expands to include his family members, some are wondering what will become of son Mark Madoff’s getaway on Nantucket, a well-heeled resort island off the Massachusetts coast. The five-bedroom waterfront home is not yet on the market, Nantucket brokers say, though a sale is entirely possible, owing to the increasing amount of trouble Mark seems to be in. “I wouldn’t be surprised if it were listed,” said Gary Winn, a principal with Maury People Sotheby’s International Realty, who has no connection to the Madoffs or the property. But the house, which Mark bought for $6.5 million in 2008, just months before Bernie’s $65 billion Ponzi scheme was exposed, was being used until recently. [more]