Extell Development held a tent party last night at its construction site for The Avery, a residential condominium building at 65th Street and Riverside Boulevard on the Upper West Side.

Entertainment was provided by Seal, the singer.

Extell and the Carlyle Group paid about $1.8 billion recently to acquire 20 acres between 59th and 65th Streets from Donald Trump and a consortium of investors from Hong Kong who have been developing properties to the north along Riverside Boulevard that ends at 72nd Street.

The Avery has been designed by Costas Kondylis and will be 30 stories high and have 274 apartments.

One-bedroom units are expected to start at about $750,000 and penthouses are priced about $3.9 million. It is expected to be completed next year.

Gary Barnett, the head of Extell, was quoted by Motoko Rich in a February 23, 2006 article in the New York Times as stating that the ?launch? party was about ?signaling that there?s new ownership and we?re doing things a bit differently.?

Extell and Carlyle are expected to erect six buildings on their property that overlooks the West Side Highway and the Hudson River.

The Avery will have a residents? theater, a gaming room, a 24-hour library with wireless Internet access, an entertaining room, a children?s playroom ?outfitted with toys, books and soft mats,? a fitness center, a garage and ?Abigail Michaels? hotel-style concierge service.?

The building will have a two-story-high lobby and kitchens will have ?ribbed aluminum upper cabinets, and Sub-Zero and Miele appliances.

Extell has recently become one of the city?s most active developers. Some of its other projects include the Orion on West 42nd Street, the Ariel East and West on Broadway at 99th Street, Altair 18 and Altair 20 in Chelsea, the W. Hotel in Times Square, and the Inter-Continental Hotel in Boston.