mats = 12G; value = 200G.. then sell it for 200 G
mats = 190G; value = 200G.. then sell it for 200G
Charge what the market will reasonably bear and make your money off of the items that have a low mat cost.
Let someone else make the collosus enchant which usually sells for a loss.
Don't list an item for 1g if the deposit is 50s and the sell chance is about 10%. You will lose money. Instead you may want to just vendor the item for the 85 silver. I am talking about green gems in particular.
Don't rely on a stupid addon to tell you what it should sell for. The addons don't have a brain.
Edited for spelling..