Check what sort of demo it is. Is it the loaner given to punters to thrash? The holy grail is the dealer principal's car. These can be red-hot specials.

Follow the warranty clock — it started the day the dealer slapped plates on it. Get the exact first registration date in writing.

The sweet spot: less than three months old, under 2000km, higher-spec model, and the discount is clearly better than a new-car deal.