HOUSTON — For six months, Sue and Roger Powell have been hoping to find a buyer for their 7,100-square-foot home in the Houston suburb of Katy. A week ago, after they waded out of it with a few suitcases on air mattresses, those hopes had largely faded. Then they got an unexpected call from their real estate agent: a house hunter was interested.

“Somebody actually called her before we got back in here,” Sue Powell said as she stood in her driveway last week, a safety mask around her neck and a pile of her possessions on the curb.

“I was really surprised,” said her husband, describing how they had “gondoliered” their way back home over Labor Day weekend. “I didn’t think anyone would be interested for years.”