hello, on average a charm in good shape will get about $10.
however sweet-n-specal is pretty rare, so if she is in good shape Id say $12-$15 if you find the right buyer *maybe* you can get $20 but dont expect that much. I have her, but if you have a nice one, PM me. I may be intrested. you shouldent have trouble selling her on here, I know there are several charm collectors after her!
the fair play Id say $10 is fair if shes in good shape, less if shes damaged. shes not too rare, so Ill see her sell under $10 on ebay now and then.
generaly said charm to charm this market can get funny, who is after them makes such a diffrence, if your looking for people to buy from I can give you contact info of a few people Ive bought from that might still have some to sell. good luck either way! its a great set, and a great trade/sale item!
~ Diana