As for the car...

K-series - good
6-speed - good
dedion - good
carbon tat - good
1.4 - bad

11k tops. at 8k it's a bargain at 10k i'd prolly buy a 1.6k instead

£13k would get you a 20K mile Superlight i'd have thought or at least a decent spec 1.6K+ 6 speed + LSD

1.4K is £10k territory and no amount of zymol or factory fitted options should convince him otherwise.

Have a look at the Classifieds on www.bookatrack.com as there are a couple there

Also keep an eye on www.findit.co.uk/cars/caterham.htm