Thanks Brian, much appreciated. I'm thankful for the credit cards being able to authorize and then capture later.
The full process is authorize, capture, then settle. The authorization is when the funds are checked against the credit card and promised as available to the business charging the cards (the merchant). Authorizations last 30 days. Our process automates the "capture" when we print the shipping label for an order. This is when we tell the credit card network ok, we're taking the money. Once a day, the network will "Settle our batch", where all captured charges are accounted for. This is when the funds transfer begins. Depending on the companies the "merchant" is paying to handle credit cards, the funds will be deposited into the merchant's checking account in one to three days.
For you, the customer, the above is consistent with "credit cards". For "debit cards", you'll need to interrogate your bank to find out what happens in the above process. From my experience, debit cards + banks = the least friendly process for the customer. They'll "take" the money from your checking account upon the authorization assuming the merchant is going to capture the funds relatively soon (like at a gas pump). In the case of my business, the capture is quick only on the simple transactions. Should a customer order the wrong part or it be a case like the group buy, that $ is gone from you the customer and can take a week to get back once I the merchant voids the authorization. That is all up to your bank and the steps they take to keep fraudsters from gaming the system.