What do I need to create a start-up?

Here's a quick list of must haves in order to create a startup, what am I missing? Go on, help me find what I need most!

1. an idea for a product or service
2. people to work with to make the project happen
3. an understanding of the need being addressed by the product/service
4. the knowledge of the customer
5. an understanding of what already exists on the market
6. an understanding of what you haven't got but you need to succeed
7. a hypothesis to validate
8. luck!