I didn't live at home during the school year. When I was home on vacations and stuff, my parents pretty much let me come and go as I pleased, although I generally told them where I was going, and what time (roughly) I'd be home. (They also knew all the people I hung out with, so they didn't have a problem with it)
Now that I've graduated, I moved home, but I have plans to move out within a year.
I don't pay rent, but I help out around the house (with my parents moving, there's been a lot of stuff that needs doing, a lot of errands that need to be run, etc), and I've also given rides to my siblings, mowed the lawn, that sort of stuff.