I had a project recently where the director was lifelong friends with a break_out star, who had committed to doing the film. The agency was non_committal. Why? Because the agency didn't want to tie_up a month of the actor's time for a measly million bucks, when they could be getting 5┦x that from a studio for the same time slot. At the end of the day, a lot of money and time was spent pre_selling territories and shoring up the financing, only to have the star drop out, under target CAA's ('er I mean a random agency's) pressure.
Second, make sure you choose the right coaching staff. When a head coach from a university comes into your living room to sell you on why you should pick their school, they usually tell you everything you want to hear. But, can they be trusted to follow up on all of their promises? You want to make sure that early on you can develop a trust with the head coach.