Odd, I run a business (not photography) that generates a little over $2m a year, and written plans are very important to what we do. 1st of all, the "running a business" model is completely different from what it was even 5 years ago and it will go though even more changes in the future. You need to at least sit and brainstorm about what your short and long term goals are. If I were to fork over $20k or $30k for equipment, buy or rent a studio and open the doors, I would not necessarily have people lined up to get their picture taken. At least get your ideas on paper and formulate a timeline and financial thought process. If you have no plan, you leave yourself open to constantly making changes along the way whose consequences or other hurdles you've not thought out yet.