Vaccinations are only necessary every three years but your vet will tell you they are necessary every year. Flea treatment is only necessary when you see fleas, your vet will tell you they need doing every month as they make good money selling the stuff. If they do have fleas ask them for Frontline spray, which is prescription only, it is expensive but actually works.
Avoid drop on neck treatments, they can cause problems for some animals and you are regularly putting unnecessary chemicals into your animal.
As for worming if they hunt then about every three months, if not only worm them if they have had fleas or you see evidence of worms in their poo or on the back of their legs under their tail (looks like grains of rice if it is tapeworm).