You would first do a P&L for the present year for your existing business and the first year and as many years after as you would like to have your plan cover. Your existing business financials will be the foundation for building yourself a business plan for as many years out as you want. This data will tell you a number of things but first if you want to build your plan around what you want in life, you would need to decide some things about your life: 1. You would need to decide how much income you would like to have for yourself for each of the years you plan for. 2. You would need to determine what kind of profit margin you would want from your business for each of the years. 3. And by combining these 2 things into a P&L format you can develop a financial business plan that can extend as for into the future as you would like. 4. The first thing it will show you is how much sales you would need each year to give you the income and profit you would like. Once you see the sales needed, if you know your business well enough, you should be able to estimate those additional expenses needed to overcome capacity constraints that will occur as your business grows.
It's like planning backwards. 1. Determine what you want in life 2. Figure out what your business would need to do to give you that life. 3. Figure out how long it would take you to reach it. 4. Figure out how big of a market it would take each of the years you're planning for. 5. Then see if that market is big enough. Isn't this a much better way to go about planning your business? Shouldn't your business be designed to give you want you want instead of you working yourself to death just hoping for the best?