AquaController 3 Pro - What its worth??

[BioSphere]

I have the opportunity to purchase a used AquaController 3 Pro with all the probes. I have no idea whats it worth. I know nothing about the controller. I wasn't even thinking of getting one until this opportunity presented itself. Any advice? What would be a fair offer?

 

[laverda]

It is hard to put a specific value without knowing more. Does it include a DC8? How old are the PH and ORP probes?
The AC3 & 3pro are super reliable and capable of doing everything most people really need? They will even do one thing you cannot do with the apex, which is control remote items via X10 modules without wires.