Are you talking about financing a car?
Someone will still finance you. It'll just wont be as fast as if you had established credit.
Also you might need to show more proof of income then just filling out the credit application at the dealer.
In other words, the lender needs to see that you really will be able to make those payments, since they don't have other type of history go by, they can't just take your word for. You must prove it.
Your interest rate will not be the best because there isn't any credit history
BUT, you can re-finance once your credit starts building up(usually after 8 payments)
Don't get a co-signer, try to do it all by yourself., you're not 18.
If you can wait 8mo-1 year, Go get a credit card and use it as a Tool To Build Your Credit Only.
Then, go finance the car you want.