Hi Kelly,
Can I suggest creating an other charge item in your item list, and call it opening balances (or something like that), point it to opening balance equity (easier for your accountant) and you can add a tax code if necessary.
Then use this item to create your open invoices and bills. That way you can use the same invoice numbers so when receiving payments/paying bills it all lines up.
If you are on a Cash basis you will need a tax code, but if you are on Accrual just leave the tax code blank.
If you need any help with this directly feel free to email me.
I also have a way that I can export and then import those open invoices/bills too if you would like someone to do it quickly for you!
Kind regards,
Sally McIntosh (sally@samsolutions.com.au)