Mr. Jette,

You definitely bring up some good points. I do agree that your own salary needs to be accounted for, however, my original intent was to show the standard operating costs ignoring that aspect, specifically because I don’t know what kind of salary you (as a store owner) would want to draw. As for opportunity cost, I agree that it’s something that needs to be considered, however, it in itself is not an operating cost it is instead in it’s own category. Lastly, the interest on the overall value of your inventory is definitely an operating cost, but it’s one that is heavily based on what you (as a store) have as your inventory that it’s cost needs to be looked at on a case by case basis (as opposed to a more over-arching review like I did here), but I definitely appreciate you bringing it up because it is another one that needs to be considered.