ween a new venture and an existing venture? What valuation models are used by investors when evaluating businesses at different stages of development?...

How does valuation differ between a new venture and an existing venture? What valuation models are used by investors when evaluating businesses at different stages of development? How does valuation differ between small companies and large companies? Why are different models used? Would these be the same valuation models used by the entrepreneur? If there are differences, why do those differences exist?