Step 1: Start saving like you said you would.
#Step 1: Start saving like you said you would. YouYou said you could stop spending, and start piling up your paychecks into your bank account. Start doing that now.
Step 2: Become an authorized user on your parents account.
#Step 2: Become an authorized user on your parents account. GetGet a credit card in your name, but don't carry it or use it. You are not spending money, remember? This will build your score without putting you in risk of getting you into costly credit card debt.
Step 3: Find a better job.
#Step 3: Find a better job. $1200$1200/month is nice spending money for a teenager, but you are almost an adult. You need to start earning more money. Try and find a job with more hours and better wages. This may mean you need to spend a little of that money you've been saving so you can go to a trade school or college.
Step 4: Once you have a comfortable emergency fund built up, start investing your money.
#Step 4: Once you have a comfortable emergency fund built up, start investing your money. YouYou don't even need to have a ton of available cash to start doing this. I recommend doing the research into how to invest it when you get to this point.
Step 5: You are now a financially responsible adult. Celebrate by buying a much cheaper used car.
#Step 5: You are now a financially responsible adult. Celebrate by buying a much cheaper used car. IfIf you have friends your age that drive expensive cars like the one you want, it is because their parents bought it, they enslaved themselves to their car payments, or they won the lottery. With your now-matured perspective on finances and wealth building, you realize that your money could be better spent (or saved) elsewhere.