You got this, man. I know when I was 16 my Dad co-signed with me on my first car. My parents didn't have any money...none...and I was working my ass off to make the payment, insurance, and put a little gas in her. It was one of those times in life where a kid starts to learn about how the real world works. It was an eye opener for me. I felt a lot of pressure to make dang sure I made enough money and budgeted right, because I knew Dad couldn't afford to bail me out and I didn't want to let him down. As much as I wish sometimes that I had opted to work awhile and save up to buy a cheap beater instead, I think it was that time in my life that really started building my work ethic. Taught me how to budget. I've been blessed (or cursed, depending on how you look at it, haha) to be a bit of a "workhorse" ever since.

Building that that responsibility for something will be good for her, but you've also made it such that it won't be a ton of pressure or burden on her either. She just has to be smart, responsible, and accountable for a couple of bills to you. Probably a good mix.

In about 13-15 years, I'm going to be a basket case myself when the little hardheaded fireball in my house wants some wheels. I think I'll buy her a couple years worth of bus tickets.