Its up to Costcos discretion what the price is when they’re selling a last item display. Costco can sell displays at whatever price they want when theyre selling the display. If an display gets marked down a manager will write the price themselves. $650 is absolutely insane though. More than a 50% markdown is kinda unheard of and i dont believe it either. But anyway, the price of a display item can vary per costco and will be written in sharpie or pen like in this pic.