Hi! I work with entrepreneurs who are exploring opportunities and launching and I lecture in Entrepreneurship on the side. The answer to your question is it depends on the purpose of your business plan and who the audience is. If it's for yourself to help you plan the business, then a good place to start is a business model canvas which quickly captures your ideas and shows you areas you need to focus on. If you are planning on going to a bank for funding, you will need the traditional 20 - 40 page business plan. Some investors will want similar, some won't. You would produce different documents to get key partners or suppliers on board. If the planning and opportunity evaluation process is new to you, you will save a lot of time and money by getting someone on board who can guide you through this process. I'm happy to jump on a call with you to help you with this.