In all three buildings, prices had soared for the two years prior to this spring.
He said that with rents close to $80 a foot and with a 2percentt vacancy in prime office buildings, prices are firm.
What You'll Pay In the neighborhood's higher-end buildings, prices have climbed faster than similar-sized units on the Upper East and Upper West Sides, brokers say.
Although building prices have tumbled in 2008, it hasn't been enough to keep investors interested.
When building prices and land values started going through the roof in '05 and '06, we stopped buying.
"It's really fancy, a condo building, prices high, has a name-brand interior designer, name-brand real estate brokerage is selling it.
Building owners argue that conditions are bad, with the vacancy rate high and rents and building prices falling because of the weak economy and the aftershocks of 9/11.
On Fifth Avenue, even in a nondescript post-World War II building, prices rise $2,000 to $3,000 a floor as you go up, Ms. Clayman said.
El Ad Properties, the developer of the Plaza Hotel, bought the building in August 2005 for $47.1 million, then resold it the next August, when building prices were at a peak, for $70.5 million to a Korean-owned developer, now known as Penterium.
As they are completed over the next 18 months, the city may be glutted with office space, depressing rents and building prices in older office districts and in other cities.
But the union argues that the industry is doing fine because, despite the recent dip, building prices and rents are far higher than they were in the 1990's.
