Tutorial on How to Create an Item for Random Payments for Zen Cart
Very useful tutorial if you need to collect or bill a customer not from an item you have in your store inventory but if someone owes you an invoice or there's any additional charge from any order and they paid through Paypal or any other online payment and has to be the customer who process it.
This is a fast and easy way without the need to install any module or add-on.
You can add attributes to the item so that customers can enter Invoice number/s, dates, or any other detail regarding to the payment.
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