Cost for teenager to buy a 2007???

Alright, so I'm 16 and want to buy my own car. Actually, I have to buy my own car. (Yay me, right?) Well, I want to buy the 2007 Pontiac Solstice. (I know, I should be looking at cars that are really old like at least 4yrs old) Of course, I need my parent's to co-signature, which will happen. So, my question is not which car I should get, but how much it would cost per month for me to finance the car. (If you don't know what the 2007 Pontiac Solstice looks like, then google it.) I'm a girl livin' in VA & I need to know how much it would cost to pay off the Solstice per month for 60 months (would I be approved to finance a car for that long?) and how much is insurance going to cost (yes, it is a 2-seater convertible).