@Jvparker 

"But open a customs report and the only available option is some thing called "Memo/Description" which does not populate with existing Memo entires but rather with downloaded bank transactions comments."

What version of QBO are you using - Simple Start?  I use QB Online Plus and have no difficulty getting data entered in the memo field of an invoice, bill, expense, bank deposit, etc., to show on a custom report.  The only exception I've found is when drilling down on an income account from the P&L.