Billionaires say a private jet is one of life's greatest luxuries. Here's how much it costs.

Even the most frugal billionaires, like Warren Buffett, have a soft spot reservered for their private jets.

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• A private jet is one of the most expensive assets money can buy.
• The costs don't end when the aircraft is purchased.
• Maintenance, crew, fuel, and a hangar can easily add up to seven figures a year.

More than 15 years ago, Oprah Winfrey shared one of her famous nuggets of wisdom: "It's great to have a private jet," she said at Duke University's 2009 commencement.