These days, that can also hold true when it comes to the plummeting real estate market. Several celebrities have dealt with foreclosure issues on their luxurious estates, and many more have had to drop their asking prices when it's time to sell.

The case of Ed McMahon has shown that you can make millions over a lengthy show-business career and still find yourself in foreclosure. Johnny Carson's former Tonight Show sidekick owes more than $644,000 in mortgage payments on his Mediterranean estate in Beverly Hills, which he and his wife have been trying to sell for two years.

The six-bedroom, five-bathroom home - in the same gated community where Britney Spears lives - is now on the market for $6.5 million, down from $7.6 million.

The 85-year-old TV personality, who has been unable to work since breaking his neck in a fall 18 months ago, described his economic problems as "a perfect storm."

"You want everything to be perfect, but that combination of the economy, I have a little injury, I have a situation. And it all came together," he said on Larry King Live.

Rick Sharga, vice president of marketing for RealtyTrac, which monitors foreclosures, says people of any income level can get in trouble by buying overvalued homes at the peak of the market that they ultimately can't afford.

"Ed McMahon's a sympathetic character in this scenario in that he got into a house that possibly he could have afforded if he had been able to keep working, then he had an injury that upset his financial apple cart pretty badly," Sharga said.

"What you don't know is, in a normal real estate market, if the same lender would have taken a look at an 82-year-old man at the tail end of his career and written him a $4.6 million mortgage he had to keeping working to be able to afford."

It's not all doom and gloom, of course. Avril Lavigne listed her nearly 6,900-square-foot Mulholland Estates mansion for $5.8 million and, after just 36 days on the market, it sold. She accepted a cash offer of $5.2 million.

But as celebrity real estate columns like "Hot Property" in the Los Angeles Times and "Gimme Shelter" in the New York Post show, other stars can't command the same prices for their houses they might have been able to a few years ago.

Mostly, what drives where a celebrity chooses to live is privacy, said Jordan Cohen of Re/Max, who has represented more than 50 stars and athletes in real estate transactions, including Marilyn Manson and Shaquille O'Neal.

He's now selling actress Joely Fisher's house - a four-bedroom, seven-bath, mid-century Craftsman at the end of a secluded drive, with a pool and a screening room - for $3.3 million, about $1 million less than the asking price when another agent first listed it last summer.

He believes a star's property can bring in more money than a regular house.

"I know it adds value," said Cohen, sitting on a limestone countertop in the kitchen of the Encino home. "A good analogy would be: Shoe companies pay athletes millions of dollars to wear a specific shoe so you'll have young America buy that shoe because a celebrity endorses it. It's the same thing with a house."

But Mark David, who follows celebrity real estate on his blog, the Real Estalker, doesn't think prospective buyers are willing to pay top dollar for houses simply because someone famous has lived in them.

"It's not common. Property values are property values," said David, 38, a graphic designer.

"You've really got to be somebody for it to add cachet. Maybe if it's a major A-list celebrity who's going to go down in Hollywood history, like Jack Nicholson. But does anybody really care about most of these people's houses? Would you pay more for Danny Bonaduce's house? And I'm not trying to bag on him. I can't imagine that people would do it - then again, there's a lid for every pot."

Bonaduce's house, by the way, is still on the market. It was listed last July for $4.5 million; now, it's down only slightly, to $4.2 million. The ornate Spanish-style mansion - with four bedrooms, 51/2 bathrooms and a theater - is just over 7,000 square feet and sits in the hills of Los Angeles' Los Feliz section.

So why not drop the price further and finally sell the property?

"He can afford to wait it out for 20 years," said Alfonso Milanese of Show4you Realty, who co-listed the home with another agent when Bonaduce and his wife, Gretchen, filed for divorce. "It's such a minuscule mortgage on there. He's one of the few people who are not in dire straits in selling their house."

As for McMahon's home, "we've actually gotten a bunch of offers," his real estate agent, Alex Davis of Hilton & Hyland, said recently. "I think we're going to sell it very soon, and that it's going to be onward and upward for the McMahons."