I keep quite a few of these running. I have three doing mold work day in and day out. I have 2 close to me in garages with phase converters mking parts in one man shops.
Be aware that they have DC drives on X, Y, and Z axis. Thus they will need brushes occasionally. The spindle drive and motor are Yaskawa AC type. Some have a gearbox and some do not. Most important is does it run and how does it sound. When was the last time the axis motors were serviced. It has a DX control. Does it still have the original mother board and hard drive or has it been upgraded. Very important also is if it was one of the early ones, does it have the Z axis PARVEX motor. It is about twice the size of the X and y motors. It has to be as there is no counter weight. How much tooling comes with the machine?