I got volunteered into playing a musical recently and playing 1st trumpet for it. I was a little surprised after the fact the amount of time committment for playing and the fact that we have 3 weekends of shows Fri/Sat/Sun. (Plus several practice sessions before hand which some times equated to a 4 hour practice to sync up with the actors.)
Interestingly enough it started off where the piano player was going to queue us in and not really have a director at first and then someone that was more of a choral non-band background is now directing us.
Needless to say there are a number of things that seem a bit unorganized and also learning about what equipment I have to supply myself among other things.
I presume you take what you get with a community theater / musical where you are playing for 'mostly' fun and not for pay or minimal pay.
Anyway I am curious as to what others have experienced with musicals.