You can support me through- https://ko-fi.com/knightmare61825

Knightmare's Shop is a server-side economy and shop mod for Forge 1.20.1 (since there were no easy shop mods for forge 1.20.1). It adds a configurable GUI shop with categories, persistent player balances, buy/sell support, bulk selling commands, player-to-player balance transfers, and built-in admin tools for editing the shop live without restarting the server. The mod is designed so normal players can use the shop immediately, while admins can manage categories, prices, items, and stack amounts from commands or a simple in-game editor.

Features

GUI-based shop with categories
Persistent player balances
Buy and sell support
Bulk inventory selling
Sell specific items by command
Transfer money between players
Live admin editing of shop data
Admin GUI editor
JSON-based config stored server-side

Installation

Install Forge 1.20.1.
Put the mod jar in the mods folder.
Start the game or server once.
The mod will generate its config file at: "config/shopmod/shop.json" That file is the main shop definition used by the mod.

Shop Config

The shop is defined in: config/shopmod/shop.json This file contains:

shop title
currency symbol
starting balance
categories
items inside each category
buy/sell prices
stack amount per transaction

Example item entry: { "item": "minecraft:diamond", "buy": 52.5, "sell": 13.13, "amount": 1 } Example category entry: { "id": "ores", "title": "Ores", "icon": "minecraft:diamond", "items": [ { "item": "minecraft:diamond", "buy": 52.5, "sell": 13.13, "amount": 1 } ] } After editing the file manually, reload it with: /shopadmin reload How Players Use the Mod Open the Shop /shop Opens the main shop menu. /shop <category> Opens a specific category directly. Example: /shop ores

Shop GUI Controls

Inside a category menu:

Left click on an item: buy one configured unit
Shift + Left click: buy a stack-sized amount
Right click: sell one configured unit
Shift + Right click: sell all matching items for that entry

Bottom bar buttons:

page navigation
back button
balance display
sell inventory button

Balance Commands: Check Your Balance /balance or /shop balance Shows your current balance.

Check Another Player's Balance /shop balance <player> Balance Transfer: Players can send money to another player. /balance transfer <player_name> <amount> Example: /balance transfer Steve 250

Rules:

amount must be greater than 0
you must have enough money
you cannot transfer money to yourself
target player must be online

Sell Commands Sell Everything Sellable in Inventory: /sellall Sells all items in your inventory that exist in the shop and have a valid sell price.

Sell All Copies of the Held Item: /sellall hand Sells every matching copy of the item currently in your main hand from your inventory.

Sell a Specific Item by Name and Quantity: /sell <item_name> <quantity> Rules:

item must exist in the shop
item must have a sell price
you must have that quantity in your inventory
quantity must match the shop entry rules
if an item is configured with amount > 1, quantity must be a multiple of that amount

Admin Commands

These require permission level 2 or operator access.

Reload Shop Config: /shopadmin reload Reloads shop.json from disk.

Admin Balance Commands

Set a Player Balance: /shopadmin balance set <player> <amount>
Add to a Player Balance: /shopadmin balance add <player> <amount>

Admin Category Commands

Create a Category: /shopadmin category create <id> <title> Example:/shopadmin category create farming Farming
Remove a Category: /shopadmin category remove <id> Example: /shopadmin category remove farming
Rename a Category Title: /shopadmin category title <id> <title> Example: /shopadmin category title farming Crop and Farm Goods
Set a Category Icon- Hold the item you want to use as the icon, then run:
/shopadmin category icon <id> Example:/shopadmin category icon farming

Admin Item Commands These commands use the item in the admin’s main hand unless otherwise stated.

Add Held Item to a Category: /shopadmin item add <category> <buy> [sell] [amount]

Meaning:

buy = buy price
sell = sell price, optional
amount = transaction unit size, optional If sell is omitted, it stays disabled. If amount is omitted, it defaults to 1.

Remove Held Item From a Category: /shopadmin item remove <category>

Set Buy Price for Held Item: /shopadmin item setbuy <category> <price>
To disable buying: /shopadmin item setbuy ores -1
Set Sell Price for Held Item: /shopadmin item setsell <category> <price>
To disable selling: /shopadmin item setsell ores -1
Set Both Buy and Sell Prices: /shopadmin item setboth <category> <buy> <sell>
Set Transaction Amount for Held Item: /shopadmin item setamount <category> <amount> Example:/shopadmin item setamount ores 16 This means that item is bought/sold in groups of 16.

Admin Listing Commands

List Items in a Category: /shopadmin list <category> Shows the category’s items, prices, and amounts in chat.

Admin GUI Editor

Open Category List Editor: /shopadmin edit Opens the admin category browser.
Open a Specific Category Editor: /shopadmin edit <category>

How the Admin GUI Works Category List Screen: Shows all categories. Click one to edit it.

Category Editor: Inside a category editor you can:

browse configured items
click an item to open its editor
add the item in your hand
set the category icon using the item in your hand

Item Editor Inside the item editor you can:

set buy price
set sell price
set transaction amount
disable buying
disable selling
remove the item

Some edits use chat input:

when prompted, type the new value in chat
type cancel to abort the prompt

Every successful edit is written back to: config/shopmod/shop.json No restart is needed.

Price Rules

buy = -1 means players cannot buy the item
sell = -1 means players cannot sell the item
both buy and sell cannot be disabled if you want the item to matter in the shop
amount must be at least 1
Example: amount: 16 sell: 8.0 This means selling one unit sells 16 items for $8.00.

Player Balance Behavior

balances are persistent
new players start with the configured starting balance
balances are stored server-side
balance changes from shop activity and transfers happen immediately

Typical Server Workflow For Players:

Run /shop
Browse a category
Buy or sell items
Use /sellall for bulk selling
Use /balance transfer <player> <amount> to send money For Admins:
Run /shopadmin edit
Open a category
Add a held item
Set buy/sell prices
Set transaction amount
Test with /shop
Use /shopadmin reload only if the file was edited outside the game

Full Command List

Player Commands:

/shop
/shop <category>
/shop balance
/balance
/balance transfer <player> <amount>
/sellall
/sellall hand
/sell <item_name> <quantity>

Admin Commands

/shopadmin reload
/shopadmin balance set <player> <amount>
/shopadmin balance add <player> <amount>
/shopadmin category create <id> <title>
/shopadmin category remove <id>
/shopadmin category title <id> <title>
/shopadmin category icon <id>
/shopadmin item add <category> <buy> [sell] [amount]
/shopadmin item remove <category>
/shopadmin item setbuy <category> <price>
/shopadmin item setsell <category> <price>
/shopadmin item setboth <category> <buy> <sell>
/shopadmin item setamount <category> <amount>
/shopadmin list <category>
/shopadmin edit
/shopadmin edit <category>

Notes

Item names in commands should generally use Minecraft ids like minecraft:diamond or plain ids like diamond
The item must exist in the configured shop to be sellable
The mod is server-side in behavior, with the shop data controlled by the server config
Admin GUI edits and command edits both modify the same shop.json

You can support me through- https://ko-fi.com/knightmare61825