I had the same problem. - I did as you suggested and created a category and then (lets use the oil filter example) listed each oil filter by it's individual SKU since QBO won't let items have the same names. Perfect, though it does create a lot of items when it should be one item quantity "40" and then a list of SKUs.

Now here's my  new problem. Lets stick with the oil filter example but in truth  I have an equipment rental business, so that's why each item is individually coded as I'm checking them in and out.  Let's say I rent out 40 oil filters - the invoice QB produces is several pages long and lists each oil filter individually with it's SKU. That's great for scanning the items in and out by # but it looks ridiculous. I can't send an invoice that long with each filter individually listed! I should be able to put it in once and say "quantity 40" however if I do that, I can't track the SKU numbers within the inventory.  The only idea I can come up with is to NOT list items individually in my inventory, and then keep track of SKUs manually outside of quickbooks in a spreadsheet and then manually input the SKUs into the invoice "description" box. Other ideas? I'd love a best of both words scenario! Thanks in advance!