Finally, when applying discount factors, where do you intend to get your discount numbers? For a company with existing debt and equity capital you can calculate WACC and use that. For a startup company you need to figure out a risk_adjusted cost of capital that makes sense. Usually this is not just a risk_free rate which only the largest companies in the world have access to. It's probably something higher.
Next, how much detail do you need in your cash flow template Excel spreadsheet at the individual line item level? Is cash from financing sufficient or do you need equity financing, debt financing, interest earned, etc. Also how do you intend to handle depreciation and amortization, since these are non_cash items that are typically added back to the income statement entries when determining the cash effect.