Automated Buying and selling system

I need an automated buying and selling system for my website. 1. I would like to have an automated delivery system on my website. My website sells virtual goods (coins) which is a game mode on fifa called ultimate team. Basically what I do do is sell and distribute these coins to people who want to buy them. Lets say some one wants to buy 100k. First they would choose the amount of coins they would like to purchase in this case 100k and click the 'place order' button. this will take them to another page where it will say you are buying 100,000 playstation coins. Under it will say "List any player on your account with a buy now price of 100,000 Coins. Enter the name of the player you have listed in the auction below". Then the buyer will search for the player and confirm that is the player he listed by clicking on the button "find Player". After they will be taken to the billing and payment page and pay for the coins. Once they have payed the system will buy their player and the coins will be deliverd to them. I need to be able to do this on xbox and playstation please. 2. Same for the selling feature. Choose amount of coins, put player online and after the player has been bought. Payment will be made Below are a couple of examples of exactly what i want. they all do the same thing. [login to view URL] [login to view URL] [login to view URL]