I go through phases of selling stuff on eboy. I'll purge a bunch of stuff and then go months without selling. You can set a reserve if you want, so if you don't get your lowest price it won't sell. Then you can relist them or take them down. You still have to pay the site for the listing, but the cost is minimal. It's per listing, not per price, to the best of my memory.
Anywho, as for scanning, I'd lay them out and shoot them with the digital camera. Much faster. I'd also break them up into groups, itemize them, etc. Sell them by team and year, or by "rookies 1981" or whatever.
I am a compulsive collector. I have two of every comic book I've ever bought since I started in the mid 80's. I stopped years ago and just buy a couple titles that I like to read. I've got some collectables that I've never even cracked open. They are all individually bagged with an acid-free backer board. I even have 5 copies of some books. But, like Chili said, the bottom fell out big time around 90-91 for comics too. And I'll tell you why: They cut their own throat. There was a particular X-Men issue that got released with the wrong ink color. They forgot one of the pigments in the mix or something. That book went throught the roof and the companies noticed that. So what did they start doing? Releasing 5 different colors of logos on an issue, knowing that people would buy 2-5 of each copy in each color. The only problem was, they made regular production quantities of all of them, so they weren't rare in any way. Long story short, you've seen the stack of boxes in my back bedroom, right? lol!
I do have some gems though. Two each 1st printings of Frank Miller's graphic novel "The Dark Knight Returns" from 86-87 era, and his "Sin City" books from around 90 or whenever.
Anywho, I'll PM with an offer to catalog/price/sell all the cards, etc. Cuz time is one thing I got plenty of...