Idea based on pitches with short or expanded (up to 15 minutes) trailers could work, because that's how it's done for independent productions looking for money

Idea based on pitches with short or expanded (up to 15 minutes) trailers could work, because that's how it's done for independent productions looking for money now. Thing is that this would work only for low budget movies and shows (up to $20 million)... I don't see how could this raise budget for a high budget movie ($200+ million) - that would need a serious coverage.