I paid $350 CDN recently for a D5 with a colour head, power supply, voltage stabilizer a 50, 75 and 135 Rodenstock lenses, 2 lens boards, and 7 neg carriers. All the equipment looked virtually new, and all the carriers were still in their original boxes and unused except for the 4x5 carrier that had light use.
$600 seems high for equipment that has been heavily used.