I have often thought a VAT / GST type system would be a great move for the US. But from the viewpoint of keeping track of it, I do wonder if I'm as for it as I thought.
I guess it's that you owe the VAT out, less the VAT in you paid when you bought. But does that mean you have to track that on every purchase? You have six identical items in stock, which you bought at six different costs, so you have to keep up with the VAT you paid on each individual item? Or can you average it out as you would the cost, using "average cost" in an accounting system. Can you use "average VAT"?