I've just had a look at a couple of online price guides – not very accurate but in my experience they normally overvalue cars. Their part exchange values for that spec car are:
Parkers: £7470
Virtual Showroom (Glasses): £8010
What Car: £6595 (04 reg), £7495 (05 reg)
So the price isn't THAT far out for a quick sale, especially as the car is yellow with silver mirrors and red lights, which will limit its appeal enormously. Could be genuine.
Would anyone here be interested in buying it if was a genuine bargain?