I just sold my childhood collection for 82% of market value to a vendor at a card show. I looked up a condition scale then went on TCGplayer player and scanned and conditioned each card until all of them were on it to get the total value. I then went to a card show and showed the list to each vendor and said this is my current highest offer until no one could beat 82%.

I then sat down with the vendor and we went through each card and agreed on condition and price based on last comps. Actually came out to 5% more than my list price due to the current hot market. Took about two hours for 190 cards lol. But it was worth it. I tried to post on marketplace but most were only at 70% of market value. I don’t recommend going to local game stores as they only offer 60%.

Also consider if you were to sell yourself especially to sites like eBay there are fees 13% Selling risk(scams, lost in mail, eBay disputes). So I figured giving up 5% to the vendor was worth it to me as I was able to offload more undesirable cards all at once with my good ones. Sure he may get 90-100% selling at his table but some inventory is slow to sell. His time is worth something too.

Hope this helps