Hello. I have achieved this before by creating Sales Receipts with the Job selected and the line items listed. However, be sure to place $0 as the price on the Sales Receipts. This will in effect attribute the whole cost of the item towards COGS and it will show up in your job profitability report. The next limitation I have reached with this is the fact that I cannot fine tune user-permissions to give my inventory staff access to the Sales module without access to sensitive customer and job information. But if you do not have any need for this separation of access, the Sales Receipt is the way to go. I saw someone suggesting a Sales Order in this thread too which is kind of the same concept.