Re: Add a subtotal first, then the % item.
Welcome and thanks for joining this conversation, @TheSweetSittter.
Allow me to chime in for a moment and help make sure that your concern is taken care of.
Just to clarify, are you referring to the QuickBooks Desktop (QBDT) Pro version? If so, the process is just the same as what my colleague @GarlynGay provided above. You can follow the same steps to add the percentage (%) below the subtotal.
For future reference, you can also check out this article for further guidance: Add, edit, and delete items.
That should get you pointed in the right direction. Please let me know how it goes or if you're referring to something else so I can get back to you. I'm always here to help. Take care and have a wonderful rest of the week!