Hi, We need to be real clear on the MTC.
First, the estimated price in the original post was for a STATIC articulated finished/painted/decaled version NOT animated by SEARAILS. The experianced modeler will be able to create the animation.
The system required for moving the crane laterally on single Z scale track, uses undertrack neomydium magnets glued to a horizontal driven tape, and metal wheel housings with free-rolling plastic Z scale wheels. we showed that at the Disney NTS.
Second, articulation modeling opportunities include the crane boom (rotate up or down), the cab under boom (forward and reverse), the gripper (up and down), and finally, the attach and detach of the gripper to container (electro-magnetics). All require very accurate reeving - Fred can comment on the prototype!
If SEARAILS were to provide the animation services the single unit price would be in the thousands.
The Heljan $750 HO scale crane fom Walther's is presently available for $399. We can't meet that injected molded price (plus it is easier to do in HO than in Z!). However, you can probably buy the crane, sacrifice the plastic model, and use the animation system as applied to the SEARAILS model.
Hope this clears things up - Look for the static model in April. The reeving is what's important and hard and frustrating, and requires a significant amount of dexterity, and electrical wiring.