Hi there, @chefstevem.
There is a monthly fee plan for processing payments through QuickBooks Online (QBO). However, it isn't the flat rate, but you'll only have a lower rate per transaction. The fee runs around $20 to $30 monthly.
We always ensure your business is a Payment Card Industry (PCI) compliant. For more information about the Standard Pricing agreed with merchants, kindly refer to this link: https://quickbooks.intuit.com/payments/legal..
I'm adding this article should you want to know how to record bank fees in QuickBooks: Enter a bank service fee while using a third-party merchant service.
I'll be here ready to lend a helping hand if you need anything. Stay safe out there.