what kind of discount on demo speakers?

30%-35%. If the ding is noticeable, you might get to 40% but if you do, you've done well. That is ballpark...clearly if the speakers are direct-from-manufacturer without huge distributors and regional sales guys taking a margin everytime, then you ought to do better. Good luck!

2000 is all I'd pay.

You cant expect demo speakers for half off even w small ding. 40% discount is LUCKY.

If you truly will have the original full warranty, I also doubt you'd be able to get away with only 2000. Generally speaking, I think 30-35% off is more realistic, and a 40% discount would be a great deal. On the other hand, the discounting potential can vary considerably depending on the manufacturer. I know of one speaker line (the TAD inspired Pioneer EX) that is very heavily discounted (35% off) brand new with full warranty. And they sure aren't junk. I've heard them, and they are excellent. So if I was buying a Pioneer EX demo, I would expect 45-50% off in such a case.