I definitely will NOT do a garage sale, but my neighborhood has an "online yard sale" page and I have sold a few items through there as well as FB marketplace, so those are all options for me too (and would save me a trip to the post office). But I'm kind of testing the waters to see how this works.
Worst case scenario, it'll be a trip to the Salvation Army to donate them. I'm sure they need toys and honestly, some of these MegaBloks sets are still unopened! It sort of hurts my heart but...well. I must get rid of some clutter!