is it possible to setup a credit system in wordpress??

Hi All,

Im trying to setup an article writing service. The website im creating for it is on wordpress and I have installed Profits theme on it.

I'v come across a problem with payments though.

I am in Pakistan and cannot accept payments via paypal (it does work here)
so im going to use 2checkout for it.

Now with using 2CO, the limitation I have is that its not feasible for me to accept transactions of less than $10 due to the fees.

What im trying to accomplish is a credit system that will credit a customer's account with the funds that they pay me on 2C0, they will then be able to use those funds/credits anytime. For example, when someone does a transaction of $10 on 2CO, the funds get added to their account which they may choose to order the articles at any time. Say they order articles worth $4 now, the system should be able to deduct that from the total and show their new balance of $6.

Does any one know of any plugins (free or paid) that have this capability?
or can anyone recommend a better way to do this?

Any tips would be of great help

Asim