I have absolutely no qualms with your explanation detailing the operation of Billable Expenses however the point I was raising was, that it appeared that your responses in this thread were contradictory.
In @cherylweb27 initial post, the question being posed - was it possible to add billable expenses to an existing invoice as they didn’t “want to send them multiple invoices for one project”, i.e. they wanted the entire project on one invoice.
Your first response clearly states “billable expenses can only be added to an invoice created from within the Customers tab”, which there is no dispute. But then you go on to say (in that same response) " I think it might be easier to simply delete the invoice and recreate one that includes the new expenses", but how can one do this if billable expenses can only be created within the Customers Tab.
You reiterate this further when in your next post “the replacement invoice will look essentially like the original one, plus the added line”, but how, billable expenses can only be created within the Customers Tab.
I put it to you that you made an assumption, that the existing invoice was also for billable expenses, whereas it was clearly stated that they wanted one invoice for one project. Hence your contradictory response. If @cherylweb27 was merely trying to amalgamate two billable expenses on to the one invoice, they wouldn’t have generated the thread based on their understanding of the issue and Manager.
So to achieve their single invoice result, they do need to you to use the chart of account workaround.
In closing you wrote “There was a lot of thought and effort that went into creating those modules” No disagreement here, but I find it a little odd that you can’t invoice both Billable Time and Billable Expenses on to the one invoice.