You're right, in that people starting out usually end up undercharging for their product. Though, all I can say without anymore information about your individual case. Is, to take what you find the cost should be and then double it. And if you can, run a A/B test while you increase your products cost to see if people are willing to pay the higher amount. And, if they are. Then increase the price until you find an equilibrium for your product where you don't lose customers because of too high of a cost. But, where you don't either undercharge for it.

Finding this balance will require some work. But, using analytics and A/B testing should help guide you towards the right price point.