One of the problems with shipping costs is that very often they consist of shipping and handling. Some sellers -- not many, but some -- actually try to make the bulk of their profit from "handling" charges. There's no set scale of charges for "handling" and sometimes the sky's the limit for these bozos. So, as the old Romans used to say, "caveat emptor": let the buyer beware. I echo the cautions of chatter and marlene.