How do I add a line for opening balance?

I am trying to create a custom report for certain control accounts. I need it to show opening balances, transactions, and final balance for the date spread specified.
Most of it is easy enough, but I can’t figure out how to get the opening balance.
I’ve spent hours looking for this on the forum and the guides are no help.
Any assistance is appreciated.

Welcome to the forum @VNeely,

Why not just use General Ledger Transactions report?

Because it doesn’t give an opening balance, just drs and crs for the period.

It does give you the opening and closing balances. You just need to make sure that your period start has an opening balance.

Please see this report output for Accounts Receivable: