I've never bought a new car in my life - the nearest I came to it was buying my current Rover 75 Connoisseur SE for £5700 when it was 3 years old and with 118000 on the clock.
I had driven it from new as a company car so knew the history. The original list price was £23k, so the book depreciation was pretty steep, unlike now when I could probably measure it in tenners a year.