I was laid off about 3 years ago and went full time on ebay to pay the bills. Or should I say attempt to pay the bills. IMO, there's only 3 ways to make big money on Ebay:
1) You have to sell more than cards.
2) Have a MASSIVE amount of stuff to sell that you picked up for next to nothing, sell it for a ton and have an insane amount of time to manage it all.
3) Get REAL lucky.
I'm by no means saying its impossible to make a big paycheck on the Bay, but you certainly need 2 of the 3 things I mentioned to happen to make it work.