commerce_billing

I'm working on a requirement to build an an e-commerce website. Commerce module provide almost everything I need for order processing except payment handling. Regarding to the requirement, payment only happens at the end of a billing cycle. After trying commerce_billy, commerce_invoice, and even invoice, I decide that I need to implement something for my project.

Since I found it pretty common to do e-commerce like this, I'd like to give the code to drupal community once I'm done. I will update project description later on.