Is it mutar lechatchila to overcharge for items when selling on an online market place. Very little information about the buyer is available and no information about the religion of the customer is available, but I believe that rov of people (in America and in the world) are goyim, so would the rov allow for overcharging?
Thank you for your question.
In general the rules of onaah apply when dealing wiht Jew and non Jews alike.
Pischei Choshen ( Onaah) chater 10 ftnt. 2.