Originally Posted by Ronaldinho
I hear you.
That being said, if they can't pay you, find a way to do the rewrite anyway. Stay involved, develop your relationship with the director, and it's fine to draw a line in the sand about the money, but don't let that poison your collaborative relationship with the director.
A project of mine appears to be coming back to life for no reason other than that a director I worked with in the past has some fresh heat and wants to take it to some new companies.
Communicate to your managers that the problem is "I'm super excited to work with this guy, want to do everything I can to help, but I literally can't afford to take the time off work."
This is absolutely the approach and mindset you have to take. If you don't do this the director will rewrite it himself. And then ask for writing credit. Don't kid yourself about this at all. Also... as was said, when a director comes to you, he is reaching out. He thinks you are the guy to do this with him. He's showing you respect a lot of writers never get on their projects and would die for. Don't give him a reason to jettison you.
All this also tells me they intend to make the film, thus exercising their option... money for you.
Work your day job if you have to... Then write at night with him. It's only a week and the benefits will last a hell of a lot longer.
Oh.... and tell your manager if they don't at least put one rewrite in future options they're fired. That's like option 101.