I understand a new person coming to a daylily site and wanting to try and buy or trade plants. I also understand not wanting to get scammed. So the person knows you have every right to turn them down, so if you feel uncomfortable with that, you could just ignore the request or explain why you feel uncomfortable or even might go so far as to explain what would make you change your mind. If it is a hard to find or expensive plant you might not want to get rid of any fans yet, but if it is something you have plenty of, you might give it a try.