it honestly so unds like you'll never make the money invested back. so maybe keep ad's out for 20 or 30k.... but plan on no one ever offering that much.
if i were you, i'd keep it and just continue pwning everyone's faces.
i'm selling my parts car...that i kept running somehow. but i'm selling it to a (close) family member and will probably continue working on it. it's beautiful when you get to continue a project...for free!
I plan on keeping MY z for a long. long time.
and maybe this time next year i might buy my cousins 91 civic hatch Si to putt putt around town so i can get some LS1 power in my zx. drool.
but yes, i think it's a shame everyone is letting their z's go :[
the only z i saw on barret jackson was a 71 240. it was advertised as the "lowest seller" at 12,000 :[
btw it looks like that z had a 3 piece spoiler at one point, and might have looked half way decent!