Mr. John McAfee, whose tattoos and tinted hair suggest an independent streak, is an extreme but telling example. For two decades, at almost every step of his career, he figured out a way to make more money.

In the late 1980s, he founded McAfee Associates, the antivirus software company. It gave away its software, unlike its rivals, but charged fees to those who wanted any kind of technical support. That decision helped make it a huge success. The company went public in 1992, in the early years of one of biggest stock market booms in history.

Over the last several years, Mr. McAfee began to put a large chunk of his fortune into real estate, often in remote locations. He bought the house in New Mexico as a playground for himself and fellow aerotrekkers, people who fly unlicensed, open-cockpit planes. On a 157-acre spread, he built a general store, a 35-seat movie theater and a cafe, and he bought vintage cars for his visitors to use.

He continued to invest in financial markets, sometimes borrowing money to increase the potential returns. He typically chose his investments based on suggestions from his financial advisers. One of their recommendations was to put millions of dollars into bonds tied to Lehman Brothers.

For a while, Mr. McAfee’s good run, like that of many of the American wealthy, seemed to continue. In the wake of the dot-com crash, stocks started rising again, while house prices just continued to rise. Outside’s Go magazine and National Geographic Adventure ran articles on his New Mexico property, leading to him to believe that “this was the hottest property on the planet,” he said.

But then things began to change.

In 2007, Mr. McAfee sold a 10,000-square-foot home in Colorado with a view of Pike’s Peak. He had spent $25 million to buy the property and build the house. He received $5.7 million for it. When Lehman collapsed last fall, its bonds became virtually worthless. Mr. McAfee’s stock investments cost him millions more.

One day, he realized, as he said, “Whoa, my cash is gone.”

His remaining net worth of about $4 million makes him vastly wealthier than most Americans, of course. But he has nonetheless found himself needing cash and desperately trying to reduce his monthly expenses.

He has sold a 10-passenger Cessna jet and now flies coach. This week his oceanfront estate in Hawaii sold for $1.5 million, with only a handful of bidders at the auction. He plans to spend much of his time in Belize, in part because of more favorable taxes there.

Next week, his New Mexico property will be the subject of a no-floor auction, meaning that Mr. McAfee has promised to accept the top bid, no matter how low it is.

“I am trying to face up to the reality here that the auction may bring next to nothing,” he said.

In the past, when his stock investments did poorly, he sold real estate and replenished his cash. This time, that has not been an option.

John McAfee is auctioning off this property in New Mexico to pay bills. His worth has fallen to about $4 million from a peak of about $100 million.

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