There are many reasons for utilizing such a document. Is the final document going to be about implementing a decision already having been reached or is it about analysis and recommendations for a newly proposed activity. As noted above, a finished document may be for internal or external purposes. Externally they are often used to solicit funding for a start_up or joint venture. Whatever the purpose, do not confuse effort with say, a marketing or a production plan.
Then the question is; is your market going to be big enough to provide you with 12꽭 leads for the next year and how many will you need each of the following years? It may be easier than you think to figure this out. You would do some research and with the aid of the U.S. Census Bureau you can roughly determine whether your plan can be supported by your market or not. So what do you think? Is it better to build a business plan around what you want in life then see how your business can maybe give you that or is it better to use a sample business plan for a small business where you are probably guessing?