<prompt> Human: Im about to buy a used car from a dealer pretty soon and am looking for advice. My Dad has helped me a bit, but doesnt know too much about buying used cars. Is it best to negotiate the total value of the car first and then the down payment monthly payments? What about the down and monthly payments, should I extend out the length of the payment? Im a new college grad and am moving, and dont want to be paying too much just on a car. I suggested to my Dad a 5 year repayment, but he kind of scoffed and recommended me to do a 4 year plan. Is it that common to pay off a used car 15,000 that quickly?  <response>: Theres a lot of good advice here. Ill share a few tricks my dealer tried to use on me when I bought my car some successful. Repeatedly asking If I can do X, will I have earned your business? - My salesman kept asking this question, and it was clearly an attempt for him to decide when I should be happy with the deal. I dodged this bullet by telling him to cut it out, hell have earned my business when Im happy with the vehicle and terms. If its a used vehicle, look at the car in the daylight. Get any service items well fix the bumpersupply matschange brakes, etc. in writing. READ THE PAPERWORK! I caught my dealership changing numbers on the paperwork after we had settled on numbers and percentages. Shady stuff; I should have walked away. Understand your insurance policy, etc. This was my first car, but I had scooter insurance. The dealer tried to tell me that I had coverage for new car purchases for 15 days. This may be true for some auto policies, but it was not true for the insurance I had, and could have caused me some problems. Dont let yourself get attached to the car just because youve been talking to the salesman for 3 hours. Your willingness to walk away is your biggest negotiating tool.This is by no means a comprehensive list, but theyre a few of the things that I encountered buying my car. 