I've been looking at birkins on eBay and noticed that sometimes there are small marks next to the Hermes Made In France stamp. Sometimes there are two dots, sometimes there is a symbol that looks like an "A" but without the horizontal line. What do they mean? Also, my dream is to own a croc birkin....can someone tell me a rough estimate of how much a birkin 30 in prosus croc retails for in the boutiques? And what is the average price for a used in great condition sold for? They are soooo beautiful I really want one!!