There are some sellers (several on this site alone by the prices they charge) that do in fact make a profit. But many many of us are moving parts we bought and used and are selling at a loss. Example was the gearset I raised the question about. I paid 750.00-800.00 for it and sold it for 550.00 minus 50.00 shipping. So uncle Sam looks at that as I made 550.00 profit. My tax forms are already eight pages for my yearly taxes. This will probable add three more pages.