Could someone direct me the best way to achieve this? Here is the scenario.

1. We create a customer within Zoho and assign him an amount to his account. For example £100.00

2. Customer logs into WordPress site using his username and password and the balance appears in there.

3. Customer can buy and sell his items on the WordPress site, using the available balance. It could be 1, 2 or 100 transactions. He can also cancel purchases/sales, so his balance gets adjusted accordingly.

Here are what I want to achieve:

1. Balance assigned to the customer updates after he leaves the WordPress site or in real time (no preference, as long as it gets updated)

2. Recording all transaction histories (things he bought, sold, cancelled purchases etc) within Zoho

Any help is highly appreciated.