If a document needs to be developed that requires input from other disciplines_Finance, HR, Property & Facilities, Marketing, Procurement/Supply Chain_ then most likely you are looking at a team building effort to get the job done. In any event, don't look at the task as only as a roadmap that leads to a profitable product or enterprise. Business plans are a great way to build team buy_in, force a thorough review of options, define objectives, establish benchmarks to judge performance, and help arrive at a plan_of_action. Ultimately, it can lead to a Project Management approach to implementing a plan and that can be as involved and detailed as is necessary.
A business plan is therefore an outline for taking an idea for a product or service and turning it into a commercially viable reality. It's a roadmap of the business you intend to start and without it you may end up getting lost on the way. It should therefore be remembered that having generated your business ideas and analyzed them to come up with the most viable idea, it's important to create a business plan for your online home business. Do you have one?