Brent Anderson, a marketing executive with another Southwest builder, Meritage Homes, said it bought 713 lots in stricken Arizona last year, and was on the verge of starting construction in a new Phoenix community called Lyon’s Gate.

Image Josh Snider and Cindy Rojas visited the lot for their home at Coronado Ranch in Las Vegas, developed by America West. Credit... Laura Rauch for The New York Times

“We’re building them because we’re selling them,” Mr. Anderson said. “Our customers wouldn’t care if there were 50 homes in an established neighborhood of 1980 or 1990 vintage, all foreclosed, empty and for sale at $10,000 less. They want new. And what are we going to do, let someone else build it?”

All of this goes contrary to the conventional wisdom, which suggests an improved market for builders is years away. Nationwide, new home sales at the beginning of this year plunged to a level below any recorded since 1963, when the figures were first officially tabulated.

Simply put, the country already has too many houses, the legacy of wide-scale overbuilding during the boom. The Census Bureau says there are two million vacant homes for sale, about double the historical level. Fewer new households, moreover, are being formed as families double up for economic reasons, putting a further brake on demand.

Even some builders agree with the pessimists when it comes to Las Vegas. Meritage Homes, for example, has largely withdrawn from the city. “We don’t think it will come back for a long time,” Mr. Anderson said.

American West is betting the opposite is true. The developer, which is privately held and is based here, builds nowhere else.

The evening under the tent with Mr. Lee was the official start of American West’s new community, called Reserve at Coronado Ranch. Before it opened, buyers began putting down money for the houses, which sell for under $300,000. “For the first time in three or four years, we have pent-up demand,” said American West’s vice president for sales, Jeff Canarelli.