Jeremy Juuso is the author of the world's best hardcore text about financing your film (a paperback all-too familiar to the first year MFA in Film students at UCF). In a recent blogpost from the Writers Store, Jeremy Juuso breaks down why filmmakers need to be crystal clear about how the money will flow if (when?) their film is sold.
Juuso is nothing if not thorough. Don't be put off by the numbers. Filmmakers who read all the way through Juuso's post (and then use his book as their template for building a business plan) will have a big advantage when it comes to the business side of the independent film business. As Juuso says, it's OK to ask questions (I'll try to respond if there are questions posted in the comments below.)
Even if you hate numbers and want to delegate all that to your lawyer or producer, the conclusion to Juuso's blogpost are words to live by: "[F]rom the start of your project, clearly define what you mean by "points," so that there is no misunderstanding later on. Clarify, in some manner or other, that any profit participation on the backend will come out of the producer's share of the investor/producer split. And if someone tries to be unclear with you by using terms like "gross," "adjusted gross," or "net," have them define exactly what they mean. The movie business is unclear enough as it is, no need to obfuscate it further. Don't just make your points, define them!"