I want inner payment system where users will have balance in credits and use them as money to buy items .
-To show you in the status the number of credits do you have.
-for every purchase you do, do not have the option to pay by direct payment or credit card but to have to buy credits and with those credits to pay the auction
-if you won an auction and do not have enough credits to have automatic option to buy as many credits you need (Show it to a box with number of credit you have to buy) or you add the number of credits you want to ill buy.