There's about a thousand factors which affect what you would pay in interest on this kind of loan. Age of the car, how long the loan is over, dealer purchased or not, your residency status, your credit score, your income...blah...blah....
So saying that, anywhere between 10% and 50%.
Good credit score, new vehicle, long residency etc.. 14% maybe.
Same for a used car maybe 18%.
Maybe as a guide, for each problem you have, add 3/4% to the rate!!
Documentation required is heavy, pretty much your life on a sheet of paper certified by the issuing authority. And they will check it all out.