client purchased but not paid, I need a function that admin can change the order info., like price, shipping cost, order quantity, payment method, etc., after that buyer can go to "my account" againt for payment if it's not paid.
Sometimes, if buyer has already paid, but he/she requested to add quantity, or requested to use other shipping way, the total amount will be different with paid, so there's a difference, I also expect there's "Still need to Pay $..." button when the order info. is changed, for buyer to make up payment.



