Here is a short guide on how to create such a shop. Notice the price is 200 coins for each Chest shop you make.
(Item name can actually be item ID or alias) – Use /iteminfo to get the ID
First line will be filled in by the plugin automatically.
Price can be pure Buy, Sell or a combination of both
You have to have B near buy price (people buy from you), and S near sell price (people sell to you).
If you have both B and S, separate them with a colon :
If the ChestShop gets created correctly, the server will automaticly fill in your playername in the first line upon creation.
Be sure to put the items in the chest below the sign or people wont be able to buy anything from you (: