I paid $500 for mine, it is an older Boss 3 model. Which has stepper motors on it. It was very easy to get it converted to Mach 3. I used a VFD to do the phase conversion for the spindle motor and I bought some Compumotor drives off ebay to run the steppers.
I am not certain what it would take to run the servos that are on that machine. I haven't had any experience with them, so I can't help you there. But I would happily spend $500 on that machine, or another just like the one I have. I use it a lot and it is a way better machine in my opinion than an import. It already has ball screws on all axis' and has a central lubrication system.