Best method to valuate a company that has negative net income.

Good Afternoon, everyone!

I have 2 inquiries related to the right selection for a method to valuate a company:

1.- Which method should I use to valuate a company that has the 2 last periods negative net income.

2.- How to valuate a company that has not started to operate - ( It stills in investment period, no cashflows until finish the investment period).

Thank you in advance.