I'm trying to sell some of my lions, but I'm not getting any takers. Did I make them too expensive? I'm new here, so I don't really know the "proper" value of many things, and I thought I was selling them for pretty cheap, but I don't know.

Can you tell me if these prices are fair, and in the future how to calculate a fair price? I checked the marketplace for similar lions, and prices are all over the place, so I really don't know if I'm doing this right.
https://www.lioden.com/trade.php?id=624885243083
https://www.lioden.com/trade.php?id=624885243081
https://www.lioden.com/trade.php?id=624885243880
https://www.lioden.com/trade.php?id=624885243491