Most People want to buy horses but they don't want to train them to level 15. Most People want to sell horses but they don't want Jorvik Shillings they want Star Coins.

It would be like the Chores Board but there would be buttons Buy or Sell a horse. They would click Buy and then they can choose from the horses that were up for sale or they would click Sell and they can choose from their horse list to sell one.