In some areas, real estate brokers were skeptical that any improvement would be sustained.

Michael Parra, a real estate agent in Las Vegas, said investors who had been fueling the market with cash purchases were starting to get cold feet, fearing values would not appreciate further as long as incomes lag and jobs are scarce.

“You’re going to have a catfish market,” Mr. Parra said. “You know, catfish stay on the bottom and they occasionally jump up to the surface.”

Economists like to caution that there is no such thing as a national real estate market. Results vary widely from place to place, and some of the biggest increases in prices have come in parts of the country hit the hardest when the housing boom turned to bust.