Oaktree Capital founder new owner of Manhattan's priciest co-op Mon May 14, 2012 7:34pm EDT (Reuters) - Oaktree Capital founder Howard Marks paid a record-smashing $52.5 million for a sprawling Manhattan apartment nestled inside what is arguably the city's most exclusive building: 740 Park Avenue. Marks and his wife, Nancy, will move into the co-op -- a spread that spans two stories and 30 rooms. The apartment comes with two libraries, eight bedrooms, 10 bathrooms, six terraces and a dining room. Plus a spare. The maintenance is $412,000 a year. The apartment is the former home of Courtney Sale Ross, the widow of the former CEO of Time Warner, Steven Ross, and the founder of the Ross School in the Hamptons. The board of 740 Park is legendary for being one of the toughest in New York City, rejecting high-profile people like the late actress Joan Crawford and the billionaire investor Nelson Peltz. The Marks' neighbors will include fellow private equity titan and Blackstone Co-Founder Stephen Schwarzman, Koch Industries Executive Vice President David Koch and Estee Lauder Chairman Ronald Lauder. Kohlberg Kravis Roberts Co-Founder Henry Kravis also lived there, as well as Jacqueline Kennedy Onassis. Brown Harris Stevens managing director Kathy Sloane handled the listing. The previous record for a co-op sale was $48.8 million in 2008. Howard Marks' office said he was traveling and unavailable for comment. Marks and his wife currently reside in Los Angeles. Reporting By Michelle Conlin