First-Time Producer Budgeting Blunders: What are the biggest traps?

Hey everyone,

I'm Nadine, a script supervisor by trade, and I'm currently looking to produce my first short film. It's a passion project (a small, character-driven piece) and I'm trying to be as thorough as possible with the budget. I’ve been trying to break down everything from crew rates to equipment rentals.

However, I keep hearing horror stories about first-time producers getting hit with unexpected costs that derail their entire project. Things like forgetting about fringe benefits entirely, or drastically underestimating the true cost of post-production. And then there's the whole marketing aspect that seems to get left out altogether.

I really want to avoid making those kinds of rookie mistakes. From your experience, what are the most dangerous and common pitfalls for first-time producers when it comes to budgeting and finances? What should I specifically be on the lookout for beyond the obvious?