From what I know Barnes & Noble does not sell any used items so it would think that they wouldn't buy them. Your best luck with selling these I don't know is in a local yard sale group.
I don't think so. But I'd call them to check. Used comics books might be accepted at your local library (if they're in good condition) or perhaps there's a teen center or a juvenile facility that might want them. As for the Legos, perhaps a daycare or Social Services might be interested, although I'd look into cleaning and disinfecting them before you donate them.
Sorry, I don't know the answer to that question. I'm sure you can call them to ask.
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