Thanks for the help!

Are you saying I need to enter a New Product Testing Item for each product or just one New Item, Non-Inventory Part, called Product Testing?

Also, I guess I am confused on creating the zero invoice, although, depending on how you answer the above question, it would make more sense. If I have just one Item called Product Testing, then how would it pull from each inventory item quantities? 

I am sure it is really simple, but I am still lost. I used to work with Quickbooks for a service industry, which was no problem, but this inventory stuff is challenging. Thanks!