Big Ticket | $23 Million for a Floor on Park Avenue

Hiroko Masuike/The New York Times The co-op at 640 Park Avenue.

A magisterial floor-through residence at 640 Park Avenue, an opulent limestone building designed by J. E. R. Carpenter as a luxury rental oasis for the millionaires of 1914, sold for $23 million and was the week’s most expensive residential transaction, according to city records. The building, at the northwest corner of Park Avenue and 66th Street, went co-op in 1946; the monthly maintenance fee for the simplex, No. 8, is $15,981.

Rife with original details like Brazilian walnut floors, Fortuny wallpaper and five marble fireplaces, the apartment originally had 18 rooms but was reconfigured 40 years ago as a five-bedroom, six-bath home with a two-room staff suite. Light streams in from all four exposures.

A private elevator landing opens onto an elaborate gallery with a fireplace, and the primary entertaining rooms â€" a corner living room, a reception room and a formal dining room â€" occupy 65 feet of frontage on the avenue. There is also a south-facing library with a fireplace.

An unusually wide corridor leads to the private bedroom wing: in addition to the corner master suite, which has a fireplace, there are four bedrooms, all with en-suite baths.

The owner of the co-op, Sue Erpf Van de Bovenkamp, an art and environmental philanthropist, died there in 2011 at age 82. The widow of Armand Erpf, a financier and adviser to several American presidents, she was the president of the Armand G. Erpf Charitable Foundation. In her salad days, she traveled to Europe, where she worked in Rome as a model for the House of Valentino, and while there appeared in several films, the most memorable being Federico Fellini’s 1960 “La Dolce Vita.”

At 13 stories, 640 Park was built as a low-rise, with a single residence on each floor, by Spencer Fullerton Weaver, who also erected the slightly less grand 630 Park Avenue on the southwest corner. But 640 Park maintains its reputation for being a bit of a pioneer as one of the first superluxury residences on the avenue, with architectural detail and amenities sufficient to draw wealthy home-seekers east of Fifth and Madison Avenues.

Residents of note include the king of the J. Crew empire, Millard S. Drexler, whose sprawling unit occupies the sixth floor. As president of the co-op board, he wields considerable clout on the residential as well as the retailing front. Like most über-luxury prewar co-op buildings in the neighborhood, 640 Park does not permit financing: ownership transfers are cash-only affairs, and with just 13 units in the building, Mr. Drexler is selective about the financial integrity of his dozen neighbors.

Nancy J. Elias and John Burger of Brown Harris Stevens and Serena Boardman of Sotheby’s International Realty handled the sale for the estate. The buyers, Stanley and Frieda Cayre, were represented by Caroline Guthrie, also from Brown Harris Stevens. Mr. Cayre, a former video, music and retailing entrepreneur, is a commercial real estate investor whose family firm is Midtown Equities.

According to Ms. Elias, the buyers intend to use No. 8 as their primary residence, and to expand the master suite by annexing two of the bedrooms.

Big Ticket includes closed sales from the previous week, ending Wednesday.