8. Model T: 16.5M units sold
This one may come as a bit of a surprise considering the Model T was produced back between 1908 and 1927 when Henry Ford first developed the modern assembly line. The Model T originally sold for less than $1,000, but later models sold for less than $300 once production really started rolling in the ’20s. The Model T made millions of Americans car owners while giving thousands of people jobs in the Detroit area.