Looking for a Supply/Demand server wide Shop plugin.

Hey,
There are many Shop plugins but many of them don't fit my servers needs. I am looking for a server Shop plugin that my players can buy and sell from via commands as long as the shop has the item in stock.

For example;
- Player 1 wants to buy Iron Bars, he types /sslist (for server shop list) and sees there are no Iron Bars in stock. Then goes offline for the night.

- Player 2 sells his Iron Bars to the server shop and receives x amount of dollars (based on what it's worth, how many he sold and how much is currently in the shop).

- Player 1 comes back online the next day and checks the server shop to see if anyone has sold Iron Bars. He sees that there are now some in stock and proceeds to purchase them.

*If there are a lot of Iron bars in the shop and player 2 decides to sell his iron bars, he will notice that he isn't getting much money because the shop has too much of that item. This is to balance out someone from flooding the shop of one item just to get rich.
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Many of the server shop plugins offer an unlimited supply of items for sale, I want it to be a bit more realistic. I don't want the richest player being able to buy whatever he pleases whenever he wants to, I'd rather him be able to buy as much as he wants as long as it's in stock.

Note that I will probably be running a separate plugin for Player to Player shops but I know most player shops barely get noticed by others thus giving them an option to sell directly to the server.

Is there anything like that out there?

Any information will be appreciated,
Thanks.

 

goldstandard is kinda like that.

 

I would like a plugin like this. Would it be hard for anypugin developers?