I am looking to automate the purchase and receipts of goods into inventory by day. The catch is that one SKU may have multiple vendors and I would like to utilize a FIFO method so that when I sell a product, I deplete the oldest inventory first and then switch to the next oldest which many be a different vendor and pool. Depending on how much is sold, we may have to "ping pong" between multiple vendors for one transaction. This is being done because the same SKU may have different burden rates depending on the vendor and I need to track it by SKU by vendor.