Iphone 3g, 8gb spares/repairs UNLOCKED +

selling my iphone 3g, i thought it second hand after beening told it was in fully working order, and only had a cracked screen, so i brought it and it collected it and looks to be they had tried fixing it them self with using a screwdriver and seprating the metal frame from the back manged to put it back to togethe, but on/off button wont hold in neither will the volume button, i replaced the screen, it powers up when connected to a charger but when you swipe to unlock it wont work, i got told it could be the touch senor but i dont have any more time or money to spend out on this phone and it has cost me enough money and im in need of a full working phone, the phone its unlocked to any network please feel free to text me after 50 or a very near offer, just want my money back for what i paid