The 350z I bought was advertised at £9995, a dec 03 plate with 30k on the clock plus GT pack. This could have been sold for a grand more, Im sure of that. I looked round the car, seemed really interested then hit him with an offer of 9k!
After going to see the car over the space of a couple of days we finally agreed a price of £9150, I think. Then I pushed for a scratch to be removed from the car and a few other little niggles, full service and MOT (which is what you should get anyway) and the car to be valeted.
Dont be afraid to go in with a low offer, be cheeky and stick to your guns! God I love haggling for stuff! ha ha you have nothing to lose, go for it!