Depends on the setting. In a realistic medieval setting, you could probably get a wagon full of rabbits, including the wagon, for a gold piece. Edit: A bit of research tells me that a chicken, which i guess is roughly equivalent to a rabbit, would coast 1-2 pence in medieval england. A penny is a really small silver coin, 240 pennies = 1 pound of silver. The best comparison i could find on the quick would value a golden guinea coin at 21 shilling, but that was in the early 18th century and apparently money changed value in the meantime and it is now 60 shillings to a pound or something. This would mean that 1 golden guinea would be worth ~ 240 pennies. All of this is based on my poor understanding of a quick read on wikipedia, but my guess is that you could get ~100-200 hens for a golden coin of reasonable size. Or probably also 100-200 rabbits. In a DnD setting where gold is really, really weird and the economy makes no sense whatsoever, who knows? But as a general idea, peasants are able to afford rabbits. So the price probably isn't that high. My suggestion to handling this kind of stuff in a DnD game where everyone has at least dozens or hundred or thousands of gold pieces is that you just assume that heroes have some small coins lying about for food and lodging, and make it basically free.
