U.S. Census Bureau (census.gov): A source for a variety of useful statistics, especially the Economic Census that comes out every 5 years.
While these are easily available online, some of them are way better than the others. A lot depends on the approach that goes into writing the business plan.
At the end of it all, hiring small business consultants would be the key to your company's overall success. You want your business to be the best that it can be. For this to happen, long-term and short-term goals must be set and these changes must be implemented in a timely manner. With this in mind, you may want to involve the business plan consultant in daily operations.
Marketing - How is the product or service priced? How will it be distributed? How will it be promoted? Will it be promoted by the venture or an outside agency? What agency? How have you determined what amount to set aside for marketing? How have you determined product or service forecasts? Possible Data Sources: on-line searches; Amazon; local outlets; trade journals; industry attorneys & accountants; salespeople.
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