I suggest that you keep your hands off that $ 250,- offer! That is way too expensive !!!!
Here in Austria they sell brand new HP S20 for approx. between € 297,- (EURO) and € 360,-. Most firms sell that scanner for € 320,- which is (considering todays exchange rate) exactly $ 281,92 (USD) !!!!!!!!!
I don´t know what they charge for a brand new HP S20 in your country, but i am sure that the price can be simular to ours here if not even cheaper.