The equity in this case is a capital investement distinct from retail goods. In every sense it is different .... from amortization to taxation. Calulating "markup" or "margin" is a different beast. In every case the gain on a market traded equity investement is caluclated from the "basis" which is the cost of aquisition plus fees. It is not derived from the sale price.
They are not both correct. Snackman is wrong.
edit; not in very case ... IN around 6.499 billion cases it is cacluated from basis ... in one other case it is apparently calculated from sale price. In either event the IRS will simply tax the gain(loss) (again based on sale less basis) and they will not bother with worrying about the "percentage gain(loss)" so at least in that case it simply does not matter other than for bragging rights.
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