Checking out our local newspaper last week (Watford Observer) there is a bit notice about vets fees.
Medivet are doing lots of half price treatments, including neutering/speying, boosters, puppy jabs and various other things.
I shall ask my vet if they are matching it, failing that, Murphy will have his boosters done at Medivet for £17 this year.
I hope others have found the same thing locally.