Swap toys/clothes for Christmas?

Frugal parents can save a bundle by shopping the local classifieds and using sites such as ThredUp where people swap children's clothing and toys with each other.  Read here in the DesNews about how a local mom does it.  Craig's List, KSL Classifieds and Freecycle are all easy to use negotiating sites.  But, be careful - there are also scam artists out there.  A negative experience on Craig's List made me skeptical because they don't help you with additional info if you get ripped off and try to find recourse.  You're on your own.  But, if you do it cautiously, you can save a bundle.