Suzanne Plunkett | Reuters
A visitor looks at Chariot by Alberto Giacometti at Sotheby's auction house in London.
McKeel Hagerty, CEO of Hagerty, the insurer of collectible cars, said that the auction total for collectible cars was $1.3 billion in 2014, up from $1.2 billion in 2013. There were 158 cars sold for $1 million or more, up from 145 in 2013.
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Yet Hagerty said that prices have gotten so high after four-straight years of increases that many buyers are starting to balk. He said prices started to soften at the end of this year, which may signal a slowdown—but not a crash—next year.
"There are still a ton of buyers out there," he said. "But no one wants to be made a fool of by overpaying. I think the market may be taking a collective inhale to see where this market goes."
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Most of the auction experts and companies in the collectibles are bullish on the collectibles market. They all point to a simple equation—there are more rich people (more than 12 million millionaires and nearly 2,000 billionaires in the world) yet a scarce number of 1960s Ferraris and Mark Rothko paintings.