Author Robert Pagliarani discusses the eight rules that allowed Paranormal Activity writer/director Oren Peli to turn $11,558 into $100 Million:

1. No excuses. There are always a million and one reasons why now is not the right time. The truth is it will NEVER be the right time. The stars will never align and you won’t get a sign from heaven. There will always be a reason why it doesn’t make sense to do it, but now is always a good time to create something in your other 8 hours.
2. Find affordable help. Oren held open casting calls in LA and found two unknowns to star in his film. You too can find great talent and they don’t have to cost a lot—can you say Elance! Sell them on the idea. Inspire them. Get them involved and give them some ownership.
3. Be flexible. Oren had a rough idea for the plot, but didn’t get bogged down in the details of a script. In fact, he didn’t have a script. When it came time to shoot the film, he told the actors to improvise. Don’t get so caught up planning and strategizing that you never actually do anything. Sometimes you have to get out there and see what happens. Make mistakes; adapt; repeat.
4. Ownership is everything. When you can take some money off the table, do it, but always keep your upside protected. Oren sold the film for $350,000. By itself, that would be a nice return, but Oren also gets to share in the profits. Unless you’re getting the offer of a lifetime, try to keep some ownership.
5. Get a cheerleader. The life of a entrepreneur can get lonely and depressing. That’s why it’s so important to get a cheerleader or two on your side. Oren got Steven Spielberg. While you may not get someone like this to back your idea, the goal is to get someone who believes in you and what you’re doing. Get them to make calls on your behalf, to open their Rolodex, and to give you advice.
6. Open to feedback. Spielberg loved Oren’s film, but he thought the ending needed a bigger kick. Even though this film was Oren’s baby, he followed the advice. You don’t have all the answers. At some point you need to take advice from others. There’s a fine line, though. Don’t take advice from someone unless you really think they know what they’re talking about. Time and time again I’ve seen entrepreneurs take advice from people they didn’t like or respect, but because they were unsure, they followed it.
7. Use other people’s money. It’s important to have some skin in the game, but whenever possible, use other people’s money. This protects you in case things don’t go as planned. That ending Oren had to re-shoot? Rather than spend more of his own money, he took $4,000 from Paramount (the film’s distributor) and re-shot it.
8. Know your audience. Paranormal Activity didn’t initially go toe-to-toe with the big budget horror flicks. Instead, they capitalized on their tech-savvy audience and launched a limited release in just 13 college towns. They then provided the audience with tools to spread the word. Focus on your market. Can they become your cheerleaders? What tools can you give them to help them spread the message?

Some great rules… but perhaps there should be a number 9 — luck.

My understanding is that the original movie was purchased by the studio with the intention of remaking it with a bigger budget. It was only after the execs saw how people were reacting to screenings of the movie that they decided to release the original film.

Link to full article at Elance