I think there is going to be a very limited market for that, It may pay to make them a low offer or wait it out.
A lot depends on who did the control, i.e. individual or recognized company?
Does it have all the documentation? You may find yourself on your own if there are severe problems and the builder is not around, hence a low offer.
I have seen the Delta-Tau CNC in operation at the US IMTS show in Chicago and it did show very impressively.
Al.
CNC, Mechatronics Integration and Custom Machine Design
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E.