If you are in high school, get a weekends or nights job. If you already have a job, get a second job. You can instantly increase your income.
When you increase your income, the bank or credit union looks more favorably at you. They think more highly of you when they see how much you work, and you earn. Bonus points if you put a lot of what you earn into a savings account. They love that! The US minimum wage pays $7.25. Many retail locations pay more than that though. Let’s use that for our math though.
We’ll say you landed a night and weekend job. You work eight hours on Saturday and on Sunday. During the week, you pick up just two half shifts. You might still be in high school, and you need a few nights for homework and a date night. You work 24 hours each week at minimum wage and you make $174 per week. Since there are five weeks in a month, you clean up, making $870 per month. Not bad for a 15-year-old. Your work will pay out your Social Security taxes and other federal taxes from your check, so you will get a bit less than that.
About one-third of your income usually goes to various taxes, but you get back a chunk of it at tax time, so let’s say $261 of that went to various taxes and your take-home pay is $609. In six months, you have a little more than $3,600. You could buy an older used car outright or keep saving for a full year. Then, you would have $7,308. Wow! You have two-thirds of the cost of a new car.