I know this is often covered but just asked my local dealer - in Newbury, Berks for cost of a standard oil service and a cambelt change (AGU engine 1.8T)
Service £129 plus vat
cambelt £400 plus vat + anything else they find!
Over £600!! Glad I am doing it myself - £105 for parts including new tensioner, pulleys and water pump!
They are well known to have the worst customer services of any dealer in this region too!