My own start came at MTV, where, for 7 months, I balanced the internship with classes at NYU and a 26 hour a week night job. The main reason is that most projects require about four years of development and a dozen or more rewrites before they ever see the screen. The only one who wins will be the lawyer. Another aspect to consider is that agents rarely sign clients unless they have at least two scripts under their belts. Same goes for production companies and studios who want to make sure the work is really yours.
Lawsuits abound in the film world.
However, should the project have any marketing potential whatsoever, you must think long term. If you decide to pay a writer, you are essentially becoming your own producer. Producers on a budget often find writers in the local film school program. Call the film dept. Not bad, since the amount is tax deductible for you.