I unloaded my wife water damaged 32gb iPhone 4s (it was mint). 2 year old toddler water bottle leaked with stroller pouch. Have no clue why she put both iPhone and water bottle in same pouch when stroller has 2 side by side pouches.
But I digress. I sold it for $230 on Craigslist. It sold fast. I basically told Craigslist people apple store at worst will charge them $150 to replace water damage 32gb 4s (I believe apple just dropped replacement fee from $199 to $149 since iPhone 5 was announced) n
So their max out of cost would be around $380-390 if they were to buy the water damage iPhone 4s 32gb
Maybe they think they can fix it? Who knows. Or replace water sensors and trick apple.
Not worth my time
So $350-400 will move 32gb 4s quickly on Craigslist. $450 maybe pushing it. U may get a sucker.