The folks who have been doing this for a while, and took the time to post their thoughts on here are not out to "hurt" the value of your Schon. It is a very nice Schon, and I would expect that it would have retailed when new in the $1400-1500 range, maybe a little more, maybe a little less.
Simply being a nice, used Schon cue does not give it collectibility. As most of the folks have said, fair market value on a used cue in excellent condition is usually around 50% of the retail value. You can deduct from that if there are finish dings/issues, thin or non-original shaft, and roll-out, etc.
Ebay is about as good a judge of the value of Schon cues as you will find, and it can be flaky there, too. I have personally sold many used Schon cues on Ebay, and you just never know what is going to happen. I have seen low-end Schon cues sell for a lot more than they should, and I have seen very nice Schon cues go for way less than they should, but not all the time. It just depends on whether or not you can get 2 people who really like the cue to bid against each other for it.
These cues (used, nice Schon cues) generally top out at around $600-700 on Ebay. They are probably the best "production" cue made, and are extremely good players...very consistent from cue to cue. Your cue would make someone an excellent player.
The best thing to do it simply set a price that you think is fair for it and list it. The market will determine whether or not the price you choose is correct for it.
Joe