Will,
There are standard accounting procedures that you are probably accustomed to, such as matching a packing slip to the PO, someone counting what was delivered for accuracy, then pairing the invoice to the PO and packing slip. You need a system to inventory the stock then cost it to jobs when pulled from stock. This all takes an investment in time and technology, and commitment to the process. For contractors that don't need to carry a large stock, the more typical approach you refer to is purchasing material for a project, costing it to that job, and any excess is returned to the shop for future use (but not formally tracked).
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Jeffrey Michael CPA CCIFP
CFO
Cippco, Inc.
Philadelphia PA
(215) 335-1401
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