If he says $160 that means that $150 for you is in the bag because it is the closest mid number and he will be willing to go down. I think it is a good deal assuming you checked it, played it, made sure the joystick on the side isn't very loose, etc. I would offer $125 and go from there. Try the "I just don't have more then that in my account so I would but I can't" trick, it worked for me.
Sean Tracey has my apologies, we all know Ozzie Guillen is an idiot. I'm rooting for you!