I think you've possibly simplified by solving a different problem to what's described in the article. The problem space described is subscription plan & pay per

I think you've possibly simplified by solving a different problem to what's described in the article. The problem space described is subscription plan & pay per use (with what sounds like might be percentage pricing as well). This is quite different from per unit billing. > Some of this complexity is self-imposed Having spent years working on invoicing & payments systems, the business will impose complexity (which you can only say no to a certain amount of) and then legal will pay you a visit and explain all the many rules that apply to billing & invoicing that vary across each country. Internationalization isn't just a tax complexity.