You need scale for all of these, right? How would you start with an entirely new product or service with no previous presence in the market?
I guess you could look at similar products but if you're targeting a new market entirely, you might have no assurances that your assumptions are correct.
You revert back to more traditional pricing methods.
Pricing was advanced field even before the internet. Everyone doing it should first study pricing at least few days to get a feel and ideas and to know what kind of pricing methods to use and how to determine the initial price and how to change it.
I guess you could look at similar products but if you're targeting a new market entirely, you might have no assurances that your assumptions are correct.