Over the last hundred years there have been many popular vehicles to sell millions of units but it's pretty amazing that one of the best selling vehicles today remains the Ford Model T which was introduced a good century ago. While obtaining cash for cars like a Model T would likely net the owner a hefty sum in the event the car was in good condition, another hugely popular car, the Volkswagen Beetle, wouldn't offer the same sort of level of sale since even fifty-year-old Volkswagens are not considered that valuable and are still easily obtained.