There is an increasing demand for repair folks as the former factor techs and true experts pass on. And for those remaining, their skills are still in great demand.
I can tell you that it takes roughly four to six hours for a proper tear down and rebuild of a Contax IIa. It's not mechanically complicated, but there are a couple of tricky parts - including one part of the reassembly that would be better suited for a person with three hands.
A correctly serviced Contax IIa is an excellent camera.