An ornate 15-room duplex at 834 Fifth Avenue, the Rosario Candela-designed bastion of international billionaires, sold for $24 million, the most expensive sale of the week, according to city records. The unit, No. 3/4C, sold for $1 million above its most recent asking price, but generosity on the part of buyers eager to establish residence at this prestigious co-op building, which accepts all-cash purchases only, is far from unprecedented. Even the financial savant Charles Schwab paid more than $2 million above the $25 million listing price for his ninth-floor apartment there. The three-bedroom three-and-a-half-bath duplex, whose amenities include a wine cellar, extensive mahogany detailing, and a seven-room suite for the staff, was sold by the estate of Walter Goldstein, a concrete mogul and the president of Underhill Industries who died in 2008. Initially priced at $27.5 million, the unit lingered on the market through the downturn until this year, when its reduction to $23 million reignited the acquisitive instincts of several billionaire suitors. The winner was Philippe Laffont, the head of Coatue, a multibillion-dollar hedge fund. The listing brokers were Ann Jeffery and Mary Rutherfurd of Brown Harris Stevens. Considered one of Candela's masterpieces, 834 Fifth has attracted high-wattage personalities since it was erected in 1931: Bing Crosby was one of the first residents. Laurance S. Rockefeller, John D. Rockefeller's grandson, moved into the penthouse and liked the building so much that he bought it outright in 1946, later converting his investment to co-ops. Mr. Rockefeller's penthouse was snapped up after his death by Rupert Murdoch, the chairman of the News Corporation, for an attention-grabbing $44 million. Earlier this year, Anne and Robert Bass expanded the contingent of resident billionaires by spending $42 million for their 12th-floor apartment. Big Ticket includes closed sales from the previous week ending Wednesday.