This is a tricky one (in my experience anyway, maybe someone else has another idea). 2 ways I’ve considered - either have the line on the SO but then close the line (manually or via script or something) so it isn’t invoiced, and mark the expense report lines as billable to pass through to the invoice. Or have the line on the SO and don’t close it, and when the expense reports come through don’t make them billable (but still tag them to the project). And then when you invoice the SO, adjust the estimated expense item amount to be the actual total based on a report of expenses or whatever (or you could update it on the SO over time, if you don’t need to keep track of the original estimated amount). Basically you don’t want to double-invoice if you have it on both the SO and the expense report, so you need to make one of them not billable (by closing the SO line, or making the expense lines not billable). The first option usually makes more sense if you need to show the customer line level expense details or receipts or something, since it draws a direct line to the invoice from the expenses. Project P&L reporting also can be different depending on your various settings, so I’d probably recommend doing a mockup of both scenarios in a SB and seeing how they look in your reporting/revenue calculation/etc, to determine if one or the other makes more sense for your needs.