I teach that you should seek to learn from competitors; obviously never copy another business's idea or what they are doing, but you can absolutely learn from their mistakes or see what they are doing and discover ways to improve it. All of that analysis belongs in your business plan: make sure you have your competitors under the microscope and make sure that is a solid chunk of your plan. That is some of the best research and information you will gather about what will make your business successful in future.
Marketing Plan: Marketing plan lays down the strategies of marketing which can lead to the success of business. These strategies are in terms of marketing mix (product, price, place and promotion). From the market feasibility study and marketing research, potential/ present demands of customers are determined which helps in understanding the profile of customers and hence help in laying down the strategies for segmentation of the market, identification of the target market laying down strategies for target market.
But do not be too paranoid, make sure you are showing it to people you trust, whose feedback you welcome and can be genuinely useful in guiding how the plan takes shape. Very often when working as individuals we get very close to certain details and miss out a big thing that has slipped your mind.
Financial plan: Financial plan indicates the financial requirements of the proposed business enterprise such as: Projected cash flows ; Projected income statement ; Projected break-even point ; Projected ratios ; Projected balance sheet ; Project report preparation.