depending on the player and your friendship with the group you may get away with buying beers at the local pub after game,
sometimes its as cheap and buying a bag of bb's for the guy
at other times you'll get it for free.
guidlines. the general rule is you break it you buy it, what I mean by that is if you break a part stock, mag, optics etc... you'll pay for replacements. most of the time internals do not fall under this because of the fact that they wear down overtime but who knows.
Cost of a rental falls under the suppliers discretion 1$-50$
"You know what the chain of command is? It's the chain I go get and beat you with 'til ya understand who's in ruttin' command here."