Auction House on Your Minecraft Server: /ah with CrazyAuctions

What an auction house is and what it needs

An auction house is a shared market: each player lists whatever they're holding, at their price, and anyone can buy it from a menu, whether the seller is online or not. The money goes to the seller's account and the item to the buyer's inventory. It's what you want if you're after trading between players without building shops.

CrazyAuctions charges in server money, not emeralds, so it needs an economy: Vault (or VaultUnlocked, its continuation) and a plugin that keeps the accounts, such as EssentialsX. Without Vault it doesn't start. How to install them and set the starting money, in the economy guide.

If you'd rather have shops you can see in the world (a villager at spawn, a sign on top of a chest), that's Shopkeepers or ChestShop. You can have both: shops for everyday things and the auction for the rare stuff.

It's a plugin: it runs on Paper (what we deliver at NapNodes) and Purpur, not on Fabric or Forge. Its author only supports the latest Minecraft version, so on servers running an old version it may not be available.

Installing it

1. Make a backup

   If your server has backups, «Backups» → create one before adding plugins.

2. Set up the economy first

   If you don't have it yet: in «Mods & plugins», install EssentialsX and VaultUnlocked (the steps are in the economy guide). Without Vault, CrazyAuctions doesn't load.

3. Install CrazyAuctions

   In «Mods & plugins», search for CrazyAuctions and press «Install». If it doesn't show up, download it from its page on Modrinth or Hangar, for your server's version, and upload it to the plugins folder from «Files».

4. Restart and test

   Press «Restart». On startup it creates plugins/CrazyAuctions with its config.yml. Join the game and type /ah: the auction menu opens, empty. If it says the command doesn't exist, check the «Console»: it's almost always Vault missing or a plugin version that isn't your server's.

Selling and bidding, step by step

There are two ways to put something up for sale, and both work with the item in your hand. At a fixed price, /ah sell 500 lists it at 500 and the first person to pay takes it. As an auction, /ah bid 100 opens a bid starting at 100: others raise the offer from the menu and, when time runs out, the highest wins.

If you're holding a stack and only want to sell part of it, the amount goes after: /ah sell 500 16 sells 16 of the 64 in your hand, and you keep the rest.

1. Open the auction

   /ah (or /ca, or /crazyauctions, they're the same). The menu opens with what's for sale, in pages; the categories button filters by armor, weapons, tools, food, potions or blocks.

2. Buy

   Click the item and confirm. If you don't have enough money, it tells you and nothing is bought.

3. Check your listings

   /ah listed shows what you have for sale; click one to take it down. /ah view and a name show what another player is selling.

4. Collect what didn't sell

   Whatever expires or you take down goes to /ah expired (or /ah collect, the same menu): click and it's back in your inventory. Collect it in time: after 10 days, it's deleted.

Default times and prices

It's all in plugins/CrazyAuctions/config.yml, in the Settings block. After changing it, /ah reload applies it without a restart (it's for operators).

Sell-Time: 2d. Fixed-price listings stay up for two days; then they move to «expired». Bid-Time: 2m 30s. Bids only last two and a half minutes by default, meant for servers with lots of people. On a server with friends, raise it to 1h or 12h, or nobody will get to bid.

Full-Expire-Time: 10d. That's how long it keeps expired or withdrawn items before deleting them for good. If your players don't log in often, give it more room, for example 30d.

Minimum-Sell-Price: 10 and Minimum-Bid-Price: 100 are the lowest prices accepted; Max-Beginning-Sell-Price and Max-Beginning-Bid-Price (1000000), the highest. Put them on the scale of your server's money: if a diamond is worth 50, a minimum of 100 to bid leaves almost everything out.

Settings:
  Sell-Time: 3d
  Bid-Time: 12h
  Full-Expire-Time: 30d
  Minimum-Bid-Price: 10

Taxes: make the auction take money out of the server

On a server with an economy, money comes in nonstop (jobs, farms, selling to the server shop) and, if it doesn't leave anywhere, everything gets more expensive. The auction is a good place for it to leave.

Auction-List-Fee is what it costs to list something, whether it sells or not (0 by default). Percent-Tax is the percentage the server keeps from each sale: with 5, someone who sells something for 1000 gets 950. Both amounts disappear: they don't go to any account.

With a small tax (5 % or a low fixed fee) nobody stops selling, and the joke listings at impossible prices go away, because now they cost something.

Settings:
  Auction-List-Fee: 20
  Percent-Tax: 5

Limits per rank and what can't be sold

By default, everyone can sell, bid and browse, and there's no limit on listings per person. To set one, the permission crazyauctions.sell. with a number after it: whoever has crazyauctions.sell.3 can only have 3 things for sale at once. If they have several, the highest counts, so you give a donor rank crazyauctions.sell.10 and that's it.

With LuckPerms you set it from the console, one command at a time: lp group default permission set crazyauctions.sell.3 true for everyone and lp group vip permission set crazyauctions.sell.10 true for the vip rank. Don't give anyone crazyauctions.bypass: it skips the limits.

The BlackList in config.yml says which items can't be sold; by default, bedrock and the End portal frame. Add whatever on your server is an exploit or an event item, with its English name in lowercase (spawner, command_block…). And Allow-Damaged-Items is false: worn tools and armor can't be sold, so nobody passes off a broken pickaxe as new.

Settings:
  BlackList:
    - 'bedrock'
    - 'end_portal_frame'
    - 'spawner'
    - 'command_block'

Admin commands

/ah reload rereads config.yml and the messages without a restart. /ah force_end_all closes every open auction at once (handy before resetting the economy or starting a new season). Both are for operators by default.

What's for sale is stored in plugins/CrazyAuctions/data.yml. If you reset the world and want to start from scratch in the auction too, close everything with /ah force_end_all, stop the server and delete that file from «Files».

If a player says they won a bid and got nothing: when it ends, the bid is only charged if the winner has that money at that moment. If they spent it before, the item goes back to the seller as expired, in their /ah expired.

Bringing the auction to life

Nobody uses an empty auction. For the first few days, list a few things yourself at reasonable prices (enchanted books, shulker shells, event items) so people see it works.

Announce the good stuff: with DiscordSRV the game chat reaches your Discord, and an «I've put an elytra on /ah» gets seen even when you're not online.

If you don't have a server yet, at NapNodes you can create a Minecraft one for free, no card, with Paper: install EssentialsX, VaultUnlocked and CrazyAuctions in «Mods & plugins» and you'll have the auction running before your friends arrive.

Frequently asked questions