I once went in to Ray's and found a pretty beat up 78 P hanging on the wall... I noodled on it for a bit and it played well, so I asked how much they wanted for it. They said $400, so I bought it on the spot. After the transaction was completed, Ray (I think it was him, he was old and ornery!) took it to his bench to tighten a knob screw or something, when the lady who previously rang me up came out from the back and said "whoops, we charged you the wrong price. We got that bass mixed up with another one, and the one you bought is actually $1200."
Looks like they pulled a Steve Harvey!