I want? I have not so good credit and when I decided that I needed a car, I went with a really cheap car, but with an interest rate of 18% which was to be expected considering my situation. I was just wondering how long do I have to keep that car before I can go and buy a car that I actually want? How long does it take for the payments that Im making on my current vehicle to affect my credit file enough to allow me be get financed for a larger amount?