Usually I'll list an item on ebay and Amazon as :
Widget:
---1PK of Widget at 100% retail
---2PK of Widget at 95% retail
---3PK of Widget at 90% retail
Each has to have it's own SKU and UPC on Amazon and eBay requires unique SKU's.

Tried creating composite item of 2 of the same item, but it says we can't create a composite out of 2 of the same??? Why???