13. 1957 Ferrari 250 Testarossa
One of the first extremely successful Ferrari race cars was the gorgeous 1957 Testarossa. The car had a 250-series V12 engine of over 300 HP that was unbeatable in the late ’50s as a result.

The success of racing models helped Enzo Ferrari sell more streetcars and establish Ferrari due to that success. Of course, every Testarossa is extremely valuable. But this one sold for almost $40 million (via Auto Blog).