About 2 years ago, I tried Drupal Commerce 2 and the module itself doesn't have comment system that a shop owner can use to make a note to let customer know and customer can also check that note in order information page.  Shop owner can decided to send notification to customer though an Email, if needed.  At that time, I decided to use Drupal Core Comment together with Rules module to create a comment form and use to communicate with customers.

Our online store doesn't have real time stock online due to integrated software with POS doesn't finish yet. So, we allow customer to place an order, then, contact them back if we really have those items in stock. We also keep those items waiting for them to pay. The problem is that, many times, customer that placed an order with us just don't want to pay at that time. They ignore it until we cancel that order. Then, they place another order a week later or so. That would be ok if it happens a couple times.

A month ago, I'm thinking about to open another online store to sell something online. My major requirement is pretty easy. Those are: - Multilanguage support - Use UTF-8 - Able to do Anonymous Checkout. (Guest Checkout / Check Out Without Account) If it's possible, a few other features I needed are : - Single page checkout - Import/Export Product