18. Mazda RX-8
The RX-8 is an interesting model that was in production from 2002 to 2012. It is a pure sports coupe with four doors and four seats, making it a practical car great for daily transport. Another intriguing feature is the famous Wankel rotary engine that is light, compact and high-revving, but also quite powerful.
The RX-8 is affordable, so even later models cost under $20,000. Be advised that the Wankel engine can be hard to maintain, but it has sharp handling, great looks, and exceptional performance makes it well worth the price.