Sales of NYC luxury residential properties flagged last week after three previous consecutive high-performing weeks.

According Olshan Realty Inc.'s latest luxury market report, the week of November 12-18 saw 14 contracts signed for properties listed for $4 million and over. That's a decline after three straight weeks of 20 or more sales.

In the report, condo sales edged out co-ops by 7 to 6.

Olshan's survey also added that last week's results marked the first time that a contract was not signed for over $10 million since September of last year.

The biggest transaction last week was a 3,500-square-foot condo at Casa 74 at 255 East 74^th Street that sold for $7,995,000. Consisting of five bedrooms and three-and-a-half baths, this Upper East Side unit comes with a large eat-in kitchen with huge windows; a marble bathroom; and a 38' x 17' living/dining area. The building's amenities include an outdoor garden, an Equinox gym, and 24-hour doorman and concierge service.

Coming in a close second was a penthouse co-op at London Terrace Towers on 410 West 24^th Street that went for $7,950,000. A description emphasized in all capital letters that this unit was available with “NO BOARD APPROVAL." This two bedroom/two-and-a-half bathroom abode carries “triple wrap terraces, quadruple exposures, ceilings of 11', a wood burning fireplace, and rare materials throughout.” There's a master suite, a kitchen with a Sub Zero refrigerator and double freezers, and a study. The description of the building said that the Mark Janson-designed penthouse was featured on the cover of Architectural Digest. As for the building itself, there's an attended lobby, garage, and a gym with an Art Deco pool.

Meanwhile, a condo at 225 West 86^th Street took the third spot for last week's top luxury transactions. Located at the Beinord building, the 3,124-square-foot, four-bedroom/four-and-a-half bathroom apartment was sold for $7,840,000. Featuring the work of renowned architect Robert A.M. Stern, the apartment was described as the epitome of “timeless glamor, luxury, and elegance.” Ten-foot ceilings, white oak floors, an eat-in kitchen, and oversized windows highlight the place. “The lavish master suite, facing peacefully into the courtyard, features an abundance of closet space and a spa-like, windowed master bathroom, richly appointed in Siberian white slab marble with radiant heated floors."

David Chiu is an associate editor at The Cooperator.