1954 Ferrari 500 Mondial Spider Series I by Pinin Farina
A 1954 Ferrari 500 Mondial Spider Series I seen at an auction, left, and at the 1954 Mille Miglia race in Italy, right.
  • Scraps of a rare 1954 Ferrari 500 Mondial Spider Series I were just sold for about $1.9 million.
  • The buyer could end up investing another $2 million just to restore the car, a Ferrari expert said.
  • In "very good condition," the model can be worth up to $4 million to $5.5 million, the expert said.

The remnants of a Ferrari 500 Mondial Spider Series I were recently sold at RM Sotheby's auction for about $1.9 million, and it may take another $2 million just to restore the car to its glory racing days, a Ferrari historian told Insider.