You may find that the easiest part is the actual writing of the plan. The real work comes in the data-gathering, which may take you a hundred hours or more, depending on what you already know or have researched. If your new venture is in an area where you've been working, you may already know about your customers, your suppliers, your marketing plan, your organizational structure, your financial and cash flow needs, equipment, inventory, and so on.
Introduction - What is the name and address of the business? Who are the principals, their titles, and their addresses? What is the nature or purpose of the business? What is your launch date? How much start-up and/or operating capital is needed?
Carrying on with the example of a coffee shop, a business plan consultant will figure out what the best location would be. They already know coffee shops do well in areas with a certain demographic in place. These include students and workers, who are within close proximity to book stores.
Small business consultants are very much on top of their game. They compile industry reports relating to the business, conduct feasibility studies, as well as studies relating to potential customers.