Being as it is only the buyer that needs "protection" (the seller would have received payment before sending anything), any additional costs (ie. shipping) should be placed on buyers shoulders.
As far as selling to newbs, I can't see the risk. They send their money first, how can you get ripped off?
With regard to building trader rating, I've had more that the one transaction, but if the person your dealing with is too lazy to give you feedback, what are you supposed to do?
Paul / Whozat