Currently, Event Temple doesn't support adding multiple Accounts to a single Booking or selecting which Account to use per Document. However, there is a workaround using Locked Documents.
How to Work Around This Limitation:
Lock Existing Documents
Documents are locked automatically when they’re sent to a guest, or
You can manually lock them by marking them as Sent or Completed.
Update the Booking's Account Info
Change the company name, address, or details on the Booking to reflect the new company/vendor.
Create a New Document
Now that your Booking reflects the new company info, generate your next document as usual.
The original (locked) documents won’t be affected.
🔒 Locking ensures that any changes you make to the Booking afterward won’t retroactively change already-sent documents.