How can I add an item that will markup and invoice? I tried making a bundle and putting in a sales item that is linked to the markup account.

Create a Service Item for "Processing Fee" and then add it to the customer invoice before processing the credit card payment.

Thank you for your response,

Will I be able to set it to a percentage or will I have to calculate it for every invoice?

Hey there, keath. 

Thanks for getting back to us. I want to share some insights about your invoice concern.

Right now, setting up the service item to a percentage rate is unavailable in QuickBooks Online. You'll need to enter the desired amount manually on every invoice.

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