“The reality is, we’re seeing conditions in home construction and home finance that are the worst since the Depression,” said Steve Fritts, associate director of risk management policy at the Federal Deposit Insurance Corporation, the government agency that insures bank deposits.

Life has been difficult for large publicly traded home-building companies as well, where stock prices have collapsed and construction sharply cut back. Yet for now, many of the public companies can meet their obligations.

“They’re better capitalized and they have cash on hand,” said Ivy Zelman, a housing analyst. “They’re in a much better position than the private builders.”

No hard count exists of precisely how many builders have gone out of business since the downturn began. According to an estimate by the National Association of Home Builders, at least 20,000 builders  about a fifth of the total nationwide  have closed up shop in the last two years.

With the industry still owing hundreds of billions of dollars in loans made at the market peak, many more face insolvency in the coming months and years. “Probably north of 50 percent will fail,” Ms. Zelman said.

Much of that borrowed money went to finance land deals that now appear to have been catastrophic miscalculations. In cities like Phoenix, where housing starts are near record lows, demand for undeveloped land has plummeted, and prices have followed.

As defaults and delinquencies rise, home builders, once prized banking customers, have become pariahs. Even builders who are up to date on their interest payments or still managing to sell houses are getting trampled, as in the case of Mr. Brown.