whats this fuel filter? And does anyone have a partnumber?
Well, as its name suggests, it filters the fuel!
But like the water pump, there is no 'scheduled' time or distance to replace it - but good practice would suggest that 40k miles is a good and cautious change, with an absolute max of 80k miles IMVHO. Part number is 1K0 201 051 C, about £25 +vat - and if you do get it changed, plan to let your fuel tank run down to about a quarter (unless you want to lose a load of precious V-Power/Tesco 99 on the workshop floor!).
I'm getting my cam belt, water pump etc done for circa £250 at a local Indy.
That is a good price!