As much as Ebay is a pain in the butt (and as much as I don't like using them either), I'd avoid dealing on SSF. A lot of folks here have some sort of entitlement issue, in that they expect you to offer them a discount at retail price or below, because they happen to "know" you on the forum.
For valuable stuff that you want to flip and make a profit, you should sell on Ebay. For everything else that you wouldn't mind selling at a loss (eg. recently released Hot Toys figures), the forum is acceptable. Of course, it's up to you

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