If I have a credit line should I use that?

No! A credit line is a fluctuating rate and consumers usually pay the minimum payment. Although this may seem logical, simply put, your vehicle may take years to pay off tying up valuable money that may be needed for other things. It makes sense to have a regular payment plan. You will know your payments and can budget accordingly. Most importantly, you can decide what you are comfortable paying and the length of time needed to pay for your loan. The payment plan is geared to suit your personal needs, with no surprises.