21. Ford Falcon
Ford introduced the Falcon in 1960 as their first compact model and it was an instant bestseller. With a modern-looking body and a nice selection of economical six-cylinder engines, the Falcon was affordable. But it was also a high-quality product, which appealed to a lot of customers. Soon, Ford introduced more powerful versions with V8 engines and a convertible body style, making the Falcon even more popular and interesting (Via Classic Cars History).
The parts are inexpensive, making the Falcon an ideal canvas for modifications. You can use everything from the Mustang in the Falcon, as well. Ford made over two million Falcons in various versions and body styles, so you should be able to find one in decent condition at an affordable price.