The limestone tower at 220 Central Park South, the most expensive residential building in New York City, and arguably the world’s most profitable, has had its first resale.

A three-bedroom aerie encompassing half the 55th floor closed at the full asking price of $33 million, which was 23 percent more than the nearly $26.8 million the unknown seller had paid in late 2019. The buyer was Igor Tulchinsky, who runs a hedge fund based in Greenwich, Conn.

The deal — the city’s biggest in the month of May — could serve as a bellwether for determining whether other apartments in the nearly sold-out condominium complex will hold their value. Right now, there is another previously owned half-floor unit, on the 36th floor, under contract, according to StreetEasy, and one available for rent.

The month’s runner-up sale, at $18 million, and the largest co-op transaction, was a duplex at 300 Central Park West, a.k.a. the Eldorado, that was sold by Kenneth Lerer, a media executive who was a founder of the HuffPost, and his wife Katherine Sailer, an interior designer.

In other notable closings, Courtney S. Ross, a wife of Steven J. Ross, who ran Time Warner, sold a penthouse in TriBeCa, while the estate of Charlene Nederlander, who was married to James M. Nederlander, a Broadway producer and theater owner, sold her Fifth Avenue apartment. Steve Eisman, the financier who made a fortune betting against subprime mortgages, and his wife, Valerie Feigen, a freelance writer, sold their Park Avenue co-op.

Also, the composer Jeff Beal and his wife, Joan Beal, bought an Upper West Side townhouse. Ara Hovnanian, the home builder, and his wife Rachel Lee Hovnanian, an artist, acquired a penthouse in SoHo.

The Central Park South apartment that sold for $33 million extends 3,211 square feet and offers panoramic views of nearby Central Park and the surrounding cityscape. Its monthly carrying costs total around $14,000.

In addition to the three bedrooms, there are three and a half bathrooms, a combined living and dining area with a fireplace, a large eat-in kitchen, and a separate laundry room, according to the listing with NestSeekers International, which included a rare video tour of the space. There are herringbone oak floors, marble finishes and 11-foot ceilings throughout the home.

The NestSeekers agent Jessica C. Campbell represented the seller, who used the limited liability company 220 March and had signed a contract for the unit back in 2015, while the building was still under construction.

Ryan Serhant, who runs his own brokerage firm, represented Mr. Tulchinsky, the buyer. He said his client saw the apartment as “a great investment.”

A sponsor unit also closed in the building: A two-bedroom, two-and-a-half apartment on the 29th floor sold for almost $16.1 million.

The complex, near Columbus Circle in Midtown Manhattan, was the most expensive condominium in 2020, with an average price per square foot of $7,039, according to CityRealty, and aggregate closed sales surpassing $1 billion. In early 2019, the nation’s highest-priced single residence was sold there, with the nearly $240 million purchase of four full floors by the hedge fund manager Kenneth C. Griffin.

The duplex at the Eldorado that sold for $18 million is on the 15th and 16th floors of the co-op building, between 90th and 91st Streets facing Central Park. It features four bedrooms and five full and two half bathrooms, along with stunning views of the Jacqueline Kennedy Onassis Reservoir from a 49-by-9-foot terrace on the upper level.

The main bedroom suite, on the lower level, contains two marble bathrooms and an abundance of closet space. Each of the other bedrooms also has an en-suite bathroom, and there is a separate laundry room.

The home had been on and off the market since last June with an asking price of nearly $20 million. The buyers were identified in property records as Richard Friesner and Aimee Telsey.

Mr. Lerer, the seller, currently runs a venture capital fund. He was the chairman and one of four founders of the HuffPost news site, which debuted in 2005. He also served as chairman of BuzzFeed and is a minority owner of the New York Mets.

Ms. Ross’s penthouse, at 7 Hubert Street, was sold through a trust for $15 million. The unit had been on the market for as much as $18.5 million last August.

The 4,262-square-foot apartment is configured with two bedrooms, including an enormous primary suite with a bathroom, dressing room and two walk-in closets. A double-sided gas fireplace sits between the bedroom and bathroom.

There is also a landscaped, wraparound terrace with views of the city skyline and Hudson River.

Ms. Ross, a philanthropist, is the founder of the Ross School, a private day and boarding school in East Hampton, N.Y. She was married to Steven J. Ross, the founder of Warner Communications, now known as WarnerMedia, who died in 1992.

The buyer used the limited liability company 712 Hubert.

The estate of Ms. Nederlander sold her 10th-floor apartment at 838 Fifth Avenue, at 65th Street across from Central Park, through an auction for just under $11.3 million. This was a sizable discount from the $27.5 million asking price when it was initially listed in 2019.

The full-floor residence extends 4,522 square feet and has three bedrooms and three and a half bathrooms, as well as a wood-paneled library, a great room with coffered ceilings, a laundry room and three fireplaces. Included in the sale was a one-bedroom, one-bath staff apartment on the first floor and a storage room in the basement.

The purchase was made through the Sherman Oaks, Calif., limited liability company Hillcrest Fifth.

Ms. Nederlander died nearly two years ago. Mr. Nederlander died in 2016; he was the chairman of the Nederlander Organization, an entertainment company that presented arena concerts and theatrical shows.

Mr. Eisman and Ms. Feigen received $11 million for their duplex at 1120 Park Avenue, at 90th Street — just below the most recent $11.75 million asking price, though a big drop from the nearly $15 million they had sought last year.

Still, they made a tidy profit, having bought the place in 2009, reportedly for $7.4 million.

The sprawling co-op home features five landscaped terraces, providing picturesque vistas of the Central Park reservoir, the East River and surrounding cityscape. There are four main bedrooms, each with an en-suite bathroom and walk-in closet or dressing room, plus a staff bedroom and bathroom off the kitchen, a laundry room, and a home office.

The new owners were listed as Andrew J. and Sarah Anne Washkowitz.

Mr. Eisman is currently a managing director and senior portfolio manager at the investment management firm Neuberger Berman. He emerged as one of the few stars of the housing crisis by shorting, or betting against, subprime mortgages. He was featured in the best-selling book about the 2007-08 financial crisis, “The Big Short.”

Among the month’s other noteworthy purchases, the Beals paid $10.3 million for a limestone townhouse on West 80th Street, near Riverside Drive. The house — five stories high and 24 feet wide — has around 8,000 square feet, with six bedrooms and six and a half baths, plus a planted rooftop terrace. The seller was Jane Corbett Flusser.

Mr. Beal, a composer for film and TV, has won five Emmy Awards, including one for original dramatic music score for Netflix’s “House of Cards.”

The Hovnanians paid $8 million for a penthouse duplex at 420 West Broadway. The 3,593-square-foot co-op unit has two bedrooms, two full bathrooms and a powder room. But the main attraction are the terraces: There’s one off the living room and kitchen on the lower level; two off the primary bedroom suite, one of which has a hot tub; and a spacious rooftop terrace. Earlier this year, the couple sold their Greenwich Village townhouse for $15.9 million.

Mr. Hovnanian is the chief executive of Hovnanian Enterprises, a home-building company based in Matawan, N.J.

And just before the long Memorial Day weekend: The British director Nicholas Stoller (“Forgetting Sarah Marshall”) and his wife, Francesca Delbanco, a novelist and screenwriter (Netflix’s “Friends from College”), paid just under $7 million for an apartment at 30 Park Place in TriBeCa.

The federal government sold an apartment for $16.8 million at 15 West 63rd Street that it had seized from Riza Aziz, stepson of the former Malaysian prime minister Najib Razak, and the producer of “The Wolf of Wall Street,” in exchange for dismissing money-laundering charges.

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