OP, here's some good advice. Whether or not you take it is your choice, but just remember this; the people giving you advice aren't kids like you wanting to look cool in a "BMW", they're adults (mostly
) who've lived and learned when it comes to the entire process of ownership of an automobile.
If your budget is $6,000 i'm making the assumption you're basically broke. Is that me taking a shot at you, is that me being an asshole? Fuck no. You're 16, you're broke. I was 16, i was broke, most people giving you advice were broke at 16. All we're trying to say is for $6,000 there are many cars that are more
realistic for you to own.
If you wanted my suggestions, i'd pick up something for $3000-4000 and use the other $2000 to put the car in near perfect operating condition. Perhaps a late 90's or early 2000's Civic, perhaps a Corolla. Will it suck driving a POS? Yes, from experience it does, but it's part of being so young. Deal with it.