Selling locally is pretty good. You can sell the card a bit cheaper than market price because no fees or shipping or anything so the buyer pays less and you get more. I try to sell locally on craigslist’s or offer up when I want to sell.
I feel like visibility is one of the major issues when selling. Choosing an obscure platform only makes the process tougher generally. Occasionally you might take advantage of well known Facebook groups or Instagram if you have a good following base. Ultimately however nothing gets the job done consistently like eBay.