5: 1987 Buick GNX
There is no denying precisely how rare the Buick GNX is. The car is one of the most iconic Buick models ever witnessed. But the value of these cars hasn’t yet peaked, and you can still snatch one up. The G-Body had a lot of potential, and the GNX took a turbocharged engine and brought the platform to the next level (via Road & Track).

The 1987 Buick GNX has many unique quirks that separate it from the other GM G-Body cars. From a performance standpoint, there was no comparison at the time. The turbocharged V6 engine is still one of the best to come out of GM. Likewise, the styling has become an iconic piece of Buick history.