according to www.NADA.com you can get about 530 as a high price. But, judging by what people generally ask, about 900-1000. But only the mentally challenged, or a suzuki rider :), will pay the asking price. So figure somewhere in the 700-800 range. Personally I would say that about 775 would be good, but any more than that and I would just pass by the add.
hope this helps
Loughty
My brother just sold an 89 KDX 200 last weekend for $900. It was a great bike, in good shape and still plenty of power. He asked for $1,000 and was talked down to $900, but I think that if he stayed firm, the guy still would have bought it. First guy that looked at it bought it. You shouldn't have a problem selling it, these bikes run forever.
When I asked how much I could get for mine, I was told about $700 tops. But mine isn't in the best condition (borken plastics, missing graphics..just cosmetic stuff). Rember, 9 times out of 10 you will get less than what you ask for.