^^Agreed. It's different everywhere. Like mieventer said, some places charge for full service (you pay for grain, hay, boarding fee, someone to clean etc). Some places you may pay a semi-full service fee that's not as expensive as full service and theres some things you must provide that they won't such as you having to clean your horses stall, or you supply the grain/hay. Other places all you pay is the boarding fee which is cheaper than any above because you do everything, all you pay is to keep your horse there you supply everything. I've never boarded so I'm not sure which would be a better choice in the long run, but use your math skills and you should be able to find which is the best.
Call around and get prices on each of the three services. Than for the two that you have to supply stuff for, add up how much everything costs and...well...see what works best for ya! Good luck.
Yeah, each place is different. Make sure that you ask, and get it in writing what is covered by the fee you are paying-that should be in a good boarding contract. What isn't in alot of contracts is how much and how often if feed and hay and cleaning is included-but I would try to get it written in when ya'll sign. I have been a boarder, employee and owner of boarding facilities, and misunderstandings are easy to come by. Putting it in writing protects everyone from "he said, she said."