stuff. You can hire a college kid to write your screenplay for next to nothing and maybe even use him for other tasks in your filmmaking. The college student usually won’t mind and it will look good on his or her resume.
Stop by your local film school or film college. A film college is full of men and women who are working hard to be professional screenplay writers. Maybe you can be the one who gives them the break they need. And since they just want to get their foot in the door in filmmaking, odds are you can hire them cheap.
If you really don’t have the budget to outsource the screenplay writing, then you can just hunker down and do it yourself. A word of caution here, this is not for everyone. There is definitely a learning curve in screenplay writing. However, there are a ton of books on this and internet filmmaking courses you can take.