Ferraris are not an easy car to lose.
Owners cherish them. Ferrari clubs and Ferrari historians record each and every vehicle number. Auction companies and private collectors are constantly scouring the world's garages for obscure Ferraris to buy and sell.
Yet once every a generation or two, a Ferrari is lost—and rediscovered.
One such "lost" Ferrari is set to be sold this weekend. It's a rare 1967 Ferrari 330 GTS. It's rusted out. The engine won't start. Parts of the car are charred from a fire. And the interior looks likes like it wouldn't even qualify for most junkyards—let alone a millionaire's garage.
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Yet despite its rough condition, it is estimated to sell at Gooding & Co.'s upcoming Scottsdale, Ariz., auction for more than $2 million.
"There is a premium right now on cars that are in original condition," said David Gooding, CEO of the automotive auction house. "For some people, this car, with its original paint and materials, is more attractive than a shiny restored car where the chrome is shining and everything is perfect."
It remains to be seen how much collectors are willing to pay for the lost Ferrari, but its story shows just how high vintage Ferrari prices are soaring, and why today's rich car collectors are increasingly valuing authenticity in cars by paying as much or more for a rusty original than one that's been rebuilt with almost entirely new parts.
The story of the 330 GTS starts in Italy. The car was sent from the Ferrari factory to Carrozzeria Pininfarina, where it was finished with polished wire, wheels, a "Celeste Blu" paint job with red and blue pinstripes and special leather upholstery.
The car was the fifth in a series of 99 GTS cars that Ferrari built. It cost around $15,000—a fortune for a car at the time.
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The Ferrari was shipped in 1967 to an importer in Greenwich, Conn., and sold to Dr. Samuel Scher, a New York City plastic surgeon. Scher was an avid car collector, with a fleet of prized Alfa Romeos, Bugattis, Rolls-Royces and Mercedes-Benzes.
Scher loved the car, and drove it 20,000 miles in less than two years. In 1969, the car caught fire and was sold at a Motor Insurance Co. auction in New Jersey.
For the next 44 years, it sat in a Pennsylvania garage. Gooding said the current owner is an unidentified private collector who had heard about the car and spent years securing it from the owner.
Gooding said that if he were the buyer, he would do "minimal" work on the car—replace the wheels, get it running again—and preserve it in its current condition.
"There just aren't many of these old Ferraris that are in truly original condition," he said. "It's pretty special."
—By CNBC's Robert Frank. Follow him on Twitter @robtfrank.