Best to post it toward the upper range and see what you get for offers etc. There's been a TVC-33 on ebay that's slowly worked it's way down to $700 that's been there for a long time. Going to some of the big photo forums is another good option.
Sometimes people are weird about certain products used. For example coming from a cycling world, no one wants to touch anything that's carbon fiber and used. It just takes one scratch, crack, deep abrasion to compromise the structure and when it fails it's catastrophic. Now tripods I'd bet any of these carbon tripods could take a ton of damage and still not fail. Transferrable warranty can help, but not if use/abuse caused the failure. So in that case very detailed pics might help. Coming from a photo world I'm always leary of used optics because I remember when people would buy 3-4 new lenses, take the best sample, and sell the poor samples. Now that digital SLR's can adjust their sensor plane by lens it's not a factor.