Is there a solution that doesn't cost a thousand dollars a year or more? I've tried a handful of "solutions" now, and I still don't have anything resembling inventory management between the three sites.
My stuff is mostly used, by the way, so I typically only have a single instance of any given product. Double selling could be problematic.
some things I've tried:
Codisto- $250 a month at my sales volume
wp-lister- causing gateway timeouts, constantly running feeds.
nembol- posting used items to amazon in "new" condition, also, requires a coder to make it work with woocommerce.