I have a similar thing happen with crags list ads I have posted when I was selling items. They contact you, say they are unable to come pick up the item, but will send you a money order plus extra for shipping. They will arrange to have it picked up but you pay the shipping fee (from the money they sent you). The e mails are obviously from someone who cannot speak very good english and I know it was a scam. It happened to me four times in a row.