well i did try a sort of private gym with the last gym i held
id say u got to charge weekly fee like normal and the coach wages for how ever many weeks the people want them for (including signing fees)
and on top of that charge a suitable amount so u are not out of pocket and make a profit
and rules only thing i can think of is make sure people stick to there own coaches etc
oh and one more thing now u can have more coaches keep sessions at a good amount
all of this advise is probably useless lol but i blame the crazy jap bloke in Ur avatar