This is a tough time for sellers who are moving for job-related reasons. Rabbi Tom Gardner, who recently accepted a job at a synagogue in Baton Rouge, La., needs to sell his one-bedroom on Riverside Drive at 101st Street. Because he has sublet the apartment before, he cannot do so again under his co-op’s rules.

He bought the apartment for less than $400,000 in 1998, and last year, he was told he could sell it for $750,000. But by the time he put it on the market at the end of April, he set the asking price at $695,000, based on advice from his broker, Susan Faber of Barak Realty. Since then, the number of similar one-bedrooms for sale in his neighborhood has grown sixfold, Ms. Faber’s colleague Antonio del Rosario said.

After getting few offers, Rabbi Gardner cut the price to $650,000. When a buyer offered him less than $600,000, the rabbi made a counteroffer of $630,000. The buyer said no.

Despite the time pressures he faces, Rabbi Gardner is reluctant to yield on what he believes is the inherent strength of the unit he owns. “I think there’s still a certain value to an apartment in a full-service building on the Upper West Side,” he said.

Other sellers are even more determined to wait for the price they want.

Three years ago, Kenneth Kuo, a concert cellist who owns music schools in Manhattan and in Greenwich and Westport, Conn., and his cousin bought a one-bedroom at 120 Riverside Boulevard at Trump Place, the building where Mr. Kuo lives in a one-bedroom penthouse. They paid about $675,000.

They have been trying to sell the investment apartment for the last six months, but they are determined not to accept less than $1 million.

Image Bruce Forrest, shown with his 4-year-old son, Alexander, says hes pleased with the deal he got on the one-bedroom he is buying on East 25th Street. Credit... Suzanne DeChillo/The New York Times

Mr. Kuo has a list of other sales in his building through the middle of 2007 that indicate the asking price for his apartment is in line with the building’s sales history. He also says that last year, he sold another one-bedroom he owned in the building for $790,000 after buying it in 2005 for about $550,000. He thinks he was justified in waiting for a high price.