Money and Sign Shops
Is a a client-optional mod that adds non-item money and player/server sign shops.
Money
Players can see how much money they have with:
/money
as well as transfer funds between players
Sign Shops
come in 4 types:
[buy]
 which takes money from the player and gives them items from the storage stock
[sell]
 which takes items from the player inventory and transfers money from the shop owner to the player
[server-buy]
which takes money from the player and gives them items (infinite stock)
[server-sell]
which takes items from the player and gives them money (infinite stock)
Shop Storage Blocks
Any block with an inventory and an itemhandler capability can be used as a shop. this includes all vanilla containers such as chests, barrels, hoppers, furnaces, etc., but also includes modded storage including machines.  (A note on Machines: the shop uses the top face as it's insert and extract face)
Activating a Shop
The first line of the shop must be one of the 4 types above (only admins can activate server shops). The second and third lines can be anything you want. A description is a good idea. The last line is the price (decimals are acceptable, no thousand operators or currency symbols though)
Next, put the items the shop should look for in the container. All items in the container are used when the shop is activated. This allows you to trade multiple items together for money, such as tool kits
once your sign is set and your items in place, right click the sign to activate it. If successful, the type and price will change color.
Viewing shop info
left click any shop to see what is for sale  (Note: if you are in creative mode this will break the sign)
shop info in the chat will give tooltips for the items for sale so items like tools and weapons can show their enchantments
Vending Items You Don't Have
Do you ever want something rare that if you had, you would never need again? Does it seem silly that you can't request that item without having it first? well this mod has a solution. By using a Book and Quill, you can write in the exact item you want in JSON format and the shop will read the book when activating your shop. Key components are the first page should start with "vending" then start your JSON on a new line. see below
Shop Protections
once a shop is activated, the container is protected from opening and destruction by anyone who is not the owner or an admin. Additionally, blocks cannot be placed adjacent to the storage block. This is to prevent other players from placing hoppers or pipes to extract items from your shop. Note that, since the protections only kick in after the shop is activated, you can set up your own machines to connect to the storage block so long as you do so before the shop is activated. This is one way to make self-sustaining shops.
API
This mod has an API Package for hooks by other mods. If you have questions about implementing this with your own mod, please contact me via discord or github(links below).
Vanilla Clients
If you want to use this purely server-side you will want to add this mod's lang file to a resource pack for your clients. Otherwise most chat messages will not be as informative to your users. you can get the lang file HERE.
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