Thanks! I'll take that as a "don't hold my breath" on prices I see online, but I might get a bite or two for some pocket cash if I am looking to sell and willing to point out my more "valuable" cards.
Our local game store buys cards at 40% of 'market value' for cash, and 60% for in-store credit. I found I had four "Force of Will" from back in the Alliance set which go for around $100, and they gave me $60 credit on the spot, so you might be able to do something similar.
I've been using an app on Android called "Delver Lens" which will scan cards and look up market value. Makes is really quick to ingest large numbers of cards pretty quickly. I scanned some 600 white cards in less than 20 minutes. I do find that it has trouble differentiating between Alpha, Beta, Revised, and Unlimited though, so sometimes it gives you wacky high numbers if it thinks it's an Alpha, but that's pretty quickly corrected.
My youngest daughter has had fantastic luck with booster packs lately and has kept a running credit balance at the store just by re-selling cards.