It all depends on what you are going to feed it on, fresh, tinned, complete. For example, I would guess if you fed a good quality complete diet a 18kg bag would last around two months (I am really guessing here), and average cost of a bag is �35, then you may want to give the dog some dog biscuits, fresh veg or meat. Do you plan to take insurance, this can cost anywhere from between �7 - �20+ per month, majority of pet insurances have a �50 excess. Initial vaccinations around �40, then annual booster around �20, plus kennel cough. Microchip �15 ish - and above all, there are lots of incidentals, and trips to the vets that fall below the excess. Puppies eat four meals a day, two meat and two milky meals up to around 4 months of age. Dog lead and collar, bowls, dog beds - at a guess, a conservative estimate of �600 in first year?