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.
But your idea may be so new that you may also need to talk to potential customers, host some focus groups, talk to an ad agency, or maybe even make a prototype and float it past some people. Be prepared to spend the time. Remember, it's not about the Plan but the Planning.
Industry Analysis - How does your product or service compare with what is currently on the market? What is the trend in the overall industry? What have been the total sales in this industry over the previous 3 to 5 years? What new products or technologies have had the biggest impact on this industry recently? What is the future outlook for these and what trends are emerging? Who are the competitors, where are they located, and how are they doing? What advantage do you offer over them? Who is buying this product or service now? Describe the typical customer for this product or service.
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.