do many of you barter?

You can only be taxed on profit. So if you are making a equal exchange there is no profit.
I'm not saying some bean counter would not try to portray it as profit but that's where you have records. Not all barters will be wind falls some will be losses. should all balance out to a no profit margin. No profit=no tax.

http://www.creators.com/lifestylefea...ax-primer.html

Fair market value should always be the Lowest price that product was available.