how to barcode a box of an item?

When I buy the items, they come in as boxes. ie. I buy 200, they are packed in 8 boxes, each box has 25. Every 5 are in a plastic bag.
When I sell the items, the quantity could be any from 1 to 10 thousand.
If the sales order wants 32, I need a box and 2 plastic bags and 2 loose items.
When I fulfill the order, I need to scan the loose item and change the quantity manually to 32. This doesn't help us to check the quantity. (This is one reason my boss wants to implement barcode). It will also slow down the picker's job.
Is there anyway I can have a barcode for 1 of the item, 5 of the item and 25 of the item? So I only need to scan the barcode on the box (NS add 25), scan the barcode on the plastic bag (NS add 5) then scan the two loose item (NS add 1+1).