Hi there, @anthonykimber.

Let me share some insights about setting up online payments in QuickBooks Online (QBO). 

When using GoCardless, we can only set up a direct debit for parent customers. This option isn't available for projects since we can't enter their email information during the setup. 

However, you can use the parent's email address when sending invoices. This way, GoCardless will collect the payment directly from their bank account even if you're using a sub-customer (project).

You can check out the screenshot below as your reference.

We can also check out this article if you need more details about the Direct Debit feature: Set up customer with Direct Debit (Go Cardless). 

Would you like some assistance checking your financial data? We can use this article as a guide: Run reports in QuickBooks Online.

Let me know if you have other questions about recording customer transactions or processing their payments in QuickBooks, @anthonykimber. If you have concerns about other areas in the program, add the details to your reply and I'll get back to you.