Patchy histor is an understatement Nig, he has had the car for 5 years and not serviced it by the looks of things...Last sevice 2008.....Thats a big worry I would say as not only a CAT but could be a potential money pit......10k feels a bit strong to me.
It's about right, silver and blue interior (not highly desirable) plus cat D and patchy history its worth £12k ish based on a non cat D car in more desirable car being in the £16k region for private sale.
The suns out so they are always going to be wirth a bit more.