But like the rest of the population, their tastes run from garish to daring, glamorous to traditional. (We are sure one can read volumes about their personalities from the homes, but we won't even try here.)
Slideshow: Home of the billionaires
The shingle-clad Massachusetts estate owned by Fidelity Investments billionaire Abigail Johnson has little in common with Oracle head Larry Ellison's mansion in Woodside, California.
We scoured public records, searched databases and leaned on local sources to identify the homes of the few dozen richest people in the US. To protect their privacy, we do not reveal addresses or surroundings, but our photographs allow you to see how they live -- sometimes in surprising ways.
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In a few instances, we went with what we believed to be the most recent addresses. We know from media reports, for example, that S.I. Newhouse of Advance Publications has lived near the United Nations in New York. His wife, Victoria, was among the residents who spoke out several years ago against Donald Trump's plan to build a view-blocking new tower. But a company spokeswoman would only confirm that he and his brother, Donald Newhouse, both maintain residences in New York City.
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A few people remain total mysteries. For example, Google founders Sergey Brin and Larry Page, recently minted billionaires, guard their privacy so closely that we only know that they probably live in Palo Alto. A Google spokesman would not comment on Brin or Page's home.Obviously, when you can spend as much as you like on a home, you can indulge passions, fantasies and quirks. We're not talking wine cellars or master bedrooms suites -- once considered the height of luxury, they are practically standard in upscale homes -- but amenities like the trampoline room in Microsoft founder Bill Gates' lakeside residence in Medina, Washington.
The Forbes 400 richest Americans list
Or, Ellison's 33-acre spread inspired by the Japanese city of Kyoto. Its man-made lake was designed to be earthquake-proof, and the buildings were constructed in traditional Japanese style, without using nails.
Location isn't always a common factor among the richest Americans, either. Although wealth tends to concentrate in specific areas, being a member of the billionaire's club doesn't automatically come with a house in Palm Beach -- though John Kluge of Metromedia does occupy a pale yellow mansion there.
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Many of the richest people on our list own houses where they grew up, or near the sources of their wealth. Sometimes those are less-than-glamorous places -- think Bentonville, Arkansas, home of Wal-Mart and several members of the Walton clan. Dell head Michael Dell's primary residence is in Austin, Texas, and Nike founder Philip Knight's is in Hillsboro, Oregon, a rural area outside of Portland, Oregon.
"He bought it in the 1970s," says Mai Truong, a local real estate broker with RE/MAX Equity Group. "Back when he bought it, that was pretty much nowhere land."
Then there is the question everyone wants to ask: How much is a billionaire's home worth?
In some instances, as much -- or more -- than one would think. Kluge's Palm Beach estate, which totals more than 21,000 square feet and sits on four acres of manicured grounds adorned with statues and reflecting pools, has a market value of more than $28 million, according to county estimates.
Ellison spent several years and more than $100 million to build his palace. Earlier this year, Gates received a property tax bill for a whopping $1.1 million, because his compound was estimated to be worth nearly $140 million. Fellow Microsoft billionaire Paul Allen, who owns a group of nearby properties valued at a little under $120 million, got off with just a $1 million charge.
But at the other end of the scale are uber-wealthy people who are uninterested in flaunting--or even, it seems, enjoying--their billions. Some of our rich-listers choose to live surprisingly modestly. Take Warren Buffett, the brains behind Berkshire Hathaway. The "Oracle of Omaha" lives in the Happy Hollow neighborhood of Omaha, Nebraska. It's not a shabby place, but he bought the gray stucco home in 1958 for $31,500. In 2003, it was assessed at just $700,000.
Members of the notoriously reclusive and low-key Mars family, heirs to the candy fortune, seem to own pretty modest digs -- John Mars lives in a McLean, Virginia, townhouse and, until a few years ago, his equally secretive brother, Forrest Edward Mars Jr, who at that time was estimated to be worth $9 billion, lived in a unprepossessing condominium in Arlington, Virginia. Of course, billionaires often own more than one home - and sometimes several -which can explain why one may seem relatively modest. Another might be an utter palace.
Truong guesses that Phil Knight's house is worth just a few million dollars, depending on the condition of his house and what it's like inside.
"There's a pool, a nice big yard," she says. "But it could be very old, very simple depending on the owner."
Who wants to live like a billionaire? Perhaps you already do.
