Assumption 3: "I know how much money I need"
You think you know how much money you will need, but in reality you don't. Virtually all entrepreneurs who prepare financials underestimate how much capital they will need. When calculating your need consider the upfront startup costs, the money required to cover your initial losses and a budget to deal with expenses surprises that always tend to appear at the most inopportune time. When you have this number recognize that you won't get it all in a single check. Savvy Angel investors will give you the money as you accomplish milestones.
If you can avoid these basic assumptions and put aside your fears, then why not try to build a big company? Our economy needs more Latino growth entrepreneurs and it needs them now!