Thanks, Spencer. I realize selling LP's is not like selling stocks on my Fidelity account. The 20% you suggest is a number that i think is in the range of reasonable.
Thanks to those who suggested Discogs. I was not aware of this site before. I tried a few LP's and it works pretty well.
I think the really labor intensive thing about selling LP's would be to show images of your actual LP''s, covers etc. If you could just list with the images provided on Discogs, and then describe any differences (e.g. "there are some stamps from the radio station on the back of the cover or the owner signed their name or slight wear and water damage on one side etc.....") then this would work. The advantage of Ebay, of course, is you are selling to a very big, international market and I often found myself bidding against very deep pocket collectors from Asia etc. who were willing to pay big (bigger) bucks than I could rationalize (supply vs. demand at work). I don't know how deep the Discogs market is.