I sent an email and the response I got was that the cards are lithographs and not worth as much as real photo cards. I know that the last three were more paper-like than card-like. He said the Hatteras one might be worth $35 if it were a real card. He said that visitors were allowed into the lighthouse if the keeper wasn't busy - he would escort them up and show them around. It was a fairly common vacation activity for tourists in the Victorian era.