I can't tell you what things normally go for, because every domain is different. I had an offer for $100 for a celebrity .com, but held firm at $150 because Sedo will take $50 as commission. After a few negotiations, the seller offered the $150, so I got the $100 profit.
I'm happy with the results, because the domain was appraised here at somewhere around the $50 price range, if I could find a fan that wanted it. I believed it was worth more, and so I stuck to that belief and got it.
It's all really luck of the draw, but as the seller, you always get to decide whether or not to accept an offer made. It doesn't cost you anything to try, so I say go for it. If the domain currently gets any traffic, park it there and make a little cash off of it as you try to sell.