Referral for a bookkeeping assistant. Walt Trock direct at [Removed by Moderator].

Hello, wtrock. 

Thank you for reaching out to the Community. In QuickBooks, we have a lot of bookkeepers or accountants in designated areas. You can visit this link to find accountants based in the US: https://quickbooks.intuit.com/find-an-accountant/. 

Also, about matching specific job expenses again with the updated past invoices, you want to enter a billable expense and add the billable expenses to the invoices.  

Enter a billable expense. Here's how: 

1. Click the + New.
2. Press the transaction (Bill, Expense, or Check) you want to create.
3. Choose the payee.
4. In the Category column, tap the expense account for the transaction.
5. Enter the description and amount of the expense, then select the Billable checkbox.
6. In the Customer column, select the customer you want to bill for this expense.
7. (Optional) Enter or make sure the markup % is correct, then select the Tax checkbox or choose a tax agency if you want to charge tax.
8. Hit Save and close.

Next, add the billable expense to the invoice. I've outlined the steps below: 

1. Click the + New.
2. Choose Invoice.
3. In the Customer dropdown menu, tap the customer you created a billable expense for. This opens the Add to invoice window.
4. Hit Add on the billable expense you want to charge to your customer.
5. Press Save and close.

 To learn more about the process, please refer to this article: Enter billable expenses. 

Additionally, learn how to categorize and match transactions you've entered. Go through this article for the detailed steps: Categorize And Match Online Bank Transactions In QuickBooks Online. 

If you have any questions about QuickBooks, you can always drop by and post your concerns. We'll make sure to assist you anytime.