How much can I get for a water-damaged iPhone?

The iPhone is a 3G and the only problems I know about it are the fact that it is water-damaged, the screen coloring is brighter than it should be(kind of a foggy look to it,) the camera does not work, and to make the power on/off button work you have to push really hard. Other than that I am unaware of any problems. How much do you think I could sell it for?