Would this be considered a fair trade???

I have a EF 100mm 2.8 Marco + after market hood that I purchased in January 2009. The lens has only been used twice and has never been outdoors. I have the original receipt, box and warranty card. Would it be a fair trade for a Canon G10 in the same condition?
What is the safest way to do trades that is fair to both parties?

It's an ok trade. Your lens new is worth more than the G10 new, but not by much. You could probably sell it and buy a used G10 and have a little money left over, but I'm not sure if it would be enough to go through the hassle. As far as the transaction is concerned I would set it up so that both parties basically ship at the same time. It boils down to a matter of trust.

as long as the g10 comes with a case, extra memory cards, extra battery, you would come out with an even trade.

lens for a g10 + $50 would be ideal.