Hi there, @AlexisR.

I can help you walk through the steps in assigning an estimate to a different account.

To assign an estimate to a different account, here's how:

1. Go to the Gear icon.
2. Click on Products and Services.
3. Choose an item and select Edit.
4. Under the Income account, select the correct account.
5. Click Save and close.

To move your estimate and keep your quote information intact, you can follow these steps:

1. Open the estimate.
2. Under the Customer dropdown, change the name to the correct project.
3. Save and close after.

When you're ready to convert your estimate to an invoice and receive payment, you can access these articles below:
 

• Convert an estimate into an invoice in QuickBooks Online
• Record invoice payments in QuickBooks Online

I'm always ready to lend a hand if you have other concerns about estimates in QuickBooks Online.

Thank you for the kind response. 

The first part of your suggestion does not apply to my situation, but the 2nd part of the answer did- thank you for the clarification. 

When modifying an estimate - 

If I use the drop down - I can change the customer and save under that new account. Great!

Then I convert to an invoice. 

After I converted to an invoice the client needs the invoice billed under a different Project Job/Customer.

If I use the drop down - I can change the customer's name but cannot save because it says:

Good afternoon, @AlexisR. 

I appreciate you coming back on this thread and giving us more details about your issue. 

I tried this in the my test account, and the system is doing the same actions. This means that the system is working properly and that's how the feature performs. 

I recommend submitting feedback to our Product Developers so they can considered improving this feature in the near future. Here's how: 

1. Go to the Gear icon in the top right-hand corner. 
2. Press the Feedback option. 
3. Enter your suggestions. 
4. Tap Next to submit your feedback. 

If you have any other questions, don't hesitate to ask. Bye for now!