@Kaarme I read it as they didn't even have time to ask for a silver or three copppers or whatever, the opening offer was one gold coin. And when they were incredulous (because it was so much) the bidder immediately adjusted upwards (since they apparently felt they were bidding on the low edge).
But yea, if they have to pluck the feathers out, one gold coin would be a good starting point to repay your friend. But if they're using natural sheddings (molts?) then I dunno.