need some help on reporting by sales rep: no matter which “amount” or “total” column fields I attempt to add, it consistently produces line item results. I want to view a report with the total of the transaction only, not each line item total on the transaction and without needing to subtotal the “amount” column because collapsing the report then hides the rest of the transactional details. What am I doing incorrectly?

So you want to see each line item in a transaction, but also see the transaction total with each line item? Have you used the “Amount (Transaction Total)” field?