and for us its $600 a year club dues which covers seminars and trials and field etc.
But then, there is gas which you pay when you go
and there is equipment - equipment will cost you a fortune at first because you need to get many things - leashes, collars, dumbbells (maybe), articles (maybe), toys, training food (which you will find you have to buy different things to see what works best), crate, etc etc etc.
But I found that after the first year I "waste" very little - i know what toys he likes, I already have all the leashes and collars I could handle and can reuse them on multiple dogs, I know what food works best and how much I need for tracking / obedience so as to not waste it etc.
It's really the cost to get started that kills you, after that its not so bad - until you get into helper work! Then there are scratch pants, sleeves, covers, etc etc and it's the same thing - now you have to keep trying new equipment to see what works for you...