There are three factors that would qualify you for a car loan in general, first; is your credit , second; Is your income and third; your down payment.
So you always need to look at those three factors closely before you apply for a loan, for example if you have good credit you may be able to get a car loan with almost $0 down and the bank may not need proof of income, but if you have issues with your credit then you will need to come strong on the other two factors which means if you don’t want to bring a large amount for down payment you will need to have a good length on the job time and a good steady income, however; if you just started your job and the income is on the low side then the down payment is your way to get a car loan.
You will need to bring a good %20 to %40 down payment depend on the car you are applying for, the reason the car may play a factor on the amount of down payment is because most of subprime banks will have a rating system to rate the desirability of financing a make of a car, most banks will prefer Honda and Toyota, Etc.. and they may not even finance high line cars such as BMW and Audi.
So if your credit is real bad you may need to save average of $3000 and look for a car that is in the $9000 ballpark that is economical and good on maintenance and preferably no more than 8 years old then your chances of getting a loan is a lot better.
And if you come to look at it, there is usually a financial reason causes the issues with the credit so if you have any financial difficulties so keep in mind an affordable car that is not expensive on maintenance with affordable payment is better for you anyway.