What age did you move in with your SO?

My boyfriend is eighteen and in college (sophomore year) and I'm seventeen now turning 18 in December and he's turning nineteen in august. We will attend the same college (I chose this college before I met him) and we plan to move in with each other.... such a cliché plan I know and if all fails we talked about who the apartment would go to etc etc. so finally how old were you when you moved in with your SO? How was it?