I haven't done anything tarot related on Ebay except to sell two decks, but part of my income comes from selling on ebay in general.
It started as a way to clear out the extra stuff in my own home, then I sold a little bit for friends and from there grew a business of parting out personal estates after I closed my beauty salon. I have customers waiting in line, but I also have other streams of income so sometimes I have a lot more things up than others.
If you have any specific questions you can PM me, I'll be glad to help if I can.
One Caveat, the gravy days on Ebay are over. Its hard work, just like any other job you might expect to get paid well for. When I started 7 years ago you could list Anything and it would sell...now that's just a fading dream.
edited to add: for some reason I thought this was in chat, I see now it's listed in Professional Tarot so I'll leave my post stand if you have any Ebay related questions, but obviously I can't speak about readings, I neither list nor buy those.