If you are on the new billing (you have Payment Plans), then follow the steps below:
Step 1 - Go to the Invoices page
Step 2 - Choose one of the Invoice selections (Current/Partial Paid/Paid/Future Invoices)
Step 3 - Select a date range (left side)
Step 4 - The Auto-Pay is in the far right column. This shows whose Auto-Pay is off or on. It will show if they have a credit card or ACH set up if it's on.