To write a business plan, first of all, you have to decide what you will produce by the printer.
There are many options. Which printer model will suit you depends on this. Then you should calculate the business model (income, expenses (initial, constant, variable), financial plan).
If you are just starting a business, we would recommend you consider the possibility of producing outdoor furniture (benches, flowerpots, fences, etc.). You can calculate the cost price easily here and organize sales quickly.
You can see examples of finished products produced by a construction printer in the
Projects section.