Huh, I must be a weirdo. I got my first car when I was around 13 years old. That's when I started Drivers Ed. It was a 1988 Oldsmobile. I upgraded when I was 17 to a 1992 Oldsmobile, then when I was 18 and headed to college, a 1997 Chevy. They were all larger, 4-door sedans.
When I was 21 I purchased my first vehicle on my own - a 2001 F-150 and then bought a 2008 Subaru Outback when I was 22. Although in between the '97 Chevy and the 2001 F-150 I drove my husband's 2003 Hyundai Tiburon because he was deployed overseas with the military and it was GREAT on gas!
I started driving when I was 9 years old and my parents regularly upgraded me cars. I think I might have to break that habit now that I'm the one paying for it, though. Haha!