If you haven't doneso already, I'd say it's time to contact Quicken Support via Chat or Phone andrequest help.(I'm not going to ask you to show us image snapshots of your invoices but rather suggest that you talk to support and let them review this issue ... who knows, you might have uncovered a bug ...)
I am having the same problem with my quicken 2017 home and business. The invoice does not reflect the current balance due on it. It just shows the original billed amount even though a parital payment has been received and reconciled. I chatted on line with 2 different customer service agents. Neither could help me. The 2nd rep told me that it works correctly on his end when he posts a partial pmt but he said he was using 2018 program and mine is 2017. But now as I am doing research I am finding it still doesn't work on 2018 version. When I email the invoice to the customer the balance does not reflect the partial pmt and the new balance.
It happens when using the PRINT>INVOICES option - selecting invoices to print and then printing those selected. They seem to reflect the proper balances when printed one-at-a-time from the form itself.
@Quicken Alex, can you explain to me why there is both a Total line and a Balance Due line in Quicken 2018 HBR? It seems redundant to have both since they equal the same amount. Why was Balance Due added in 2018? It should be one or the other. FWIW, a partial payment will reduce the Balance Due but it should be on the Statement not the Invoice.Greg
How is your B&B business structured? Is it a Sole Proprietorship? I don't think Quicken 2018 HBR was designed to be used in a B&B.