Are you talking about an adjustment by applying a Debit Memo to an invoice (increasing the balance)?  That is a separate transaction, and cannot  be combined to print within the PDF for the original invoice (using regular Sage 100).  You'd have to credit everything, and create one invoice with all the details, or come up with some kind of custom report.

I typed in the Original Invoice number and customer number and it asked if I would like to adjust the Invoice and I said yes

And then I went to the totals tab and added the $495 on the freight line that was not on the original Invoice

Yes I am attempting to increase the balance on the freight line.

The same rules apply (...a DM is when you have the SO module). 

The adjustment is a separate transaction.

You can see this more clearly on the Invoices tab of customer maintenance.  Click the invoice and look at the lower grid.  An adjustment affects the balance, but the original transaction is otherwise unchanged.

Yes that is what I see on my end. And each has the Invoice number but prints as individual Invoices (separate totals). So it looks like the only way to have them combined to be printed is your original suggestion of crediting off the original Invoice and doing another Invoice to have the freight and line items print on the same page. I understand from an accounting perspective what is happening, but the customer wants in your example above to see a total of $914.25 on the Invoice sent to them (not 1 for 50 and 1 for 864.25).

Thank You for your help we just migrated from Sage 50 at the start of the year.