You can run a report for Unbilled Costs by Job as well as the Time by Job report in QuickBooks Desktop. Use these report as your reference and create an invoice for each customer:job with unbilled expenses. Then, use the Add Time & Costs button to remove the unbilled expenses.
Here's a step-by-step guide on how to achieve this:
Let's open the report and go to Reports. Then,choose Customers & Receivables.
Select Unbilled Costs by Job.
Take note of one customer with unbilled expenses and create an invoice for it.
Go to Customers menu and click Create Invoices.
Fill in the Customer:Job and click the Add Time & Cost icon.
A Billable Time/Costs window will open. Mark the Select the outstanding billable time and costs to add to this invoice? option and click OK.
Click each tab to see all unbilled entries.
Click the Hide column for each unbilled entries. Then, click OK.
Now, here's how to run the Time by Job report, you'll need to enable the Time Tracking feature through the Preferences window. I'll show you how below:
Click the Edit tab at the top menu bar.
Click Time & Expenses.
Go to the Company Preferences tab.
Below Do you track time?, click Yes.
Once done, the Time by Job reports will now show on the Jobs, Time & Mileage section.
I can only imagine how much effort you will be needing to complete this task. Please know that we are working on to come up with an easier and more convenient way to remove those unbilled expenses given the amount of date that you're working on.
Feel free to comment below if you have further questions. I would appreciate the opportunity to help you with your concerns.