There isn't a "going rate" people are just over charging for new game items. I give people anything they want for 100 fg, even that's too much for something I can just dupe, but I wouldn't log into a game to trade for less. As for runes I do like 25 fg per million. Full collections of ashes of war, talismans, max upgraded weapon tab, etc. Those go for more but they take a lot of time to drop