Also my killer move whenever I buy a car new or second hand from dealer, is to get the best price you can, and at the point of signing the contract, stop, look worried, and then push the contract back across the desk to the salesman and then carefully place the pen on the desk between the contract and the salesman saying " I just don't know if I can spend this much" - pause for a moment - then say " I there anything else you can do ?"
This works every time and the look on the salesman's face is priceless. I have had free guarantees, extra carpets, tow bars, extra cash discounts, higher trade in value on the old car, and often a combination of these. When I got a new elise I used my trick and then got leather seats and a detachable motorsport steering wheel for free, (these were the only available extras), a free labour cost on the second service and an extra £250 trade in on and old banger I wanted to get rid of. And this was on a car that had a waiting list....... salesman are suckers !!!!!