i haven't "SOLD" anything in a year or so.
it seems the pro sellers flood the market with multiple listings of the same thing and they apply "FITS" advisement on everything, this way their cheese grader ends up on a search for hemi piston rings. this seems to put the average seller at a disadvantage because their listings get buried this way.

i actually have my best luck with a auction listing for a week. if you list buy it now with no end date you will end up on the bottom of a 10000+ of listings.

when i sell i add shipping costs into the sale price. you will still have to pay a fee on in anyways if you charge extra for it anyway.

figure 15% of the price for ebay and payment fees,