Dead C128Ds do exist! Mine has a knackered 1571 drive ..... last time I used it I had to resort to the good old 20+ y.o. Datasette.
It is a fact that I have
no C128-mode applications on casette tape!!
Its worth looking out for a Dead C128D ..... the case is really well designed. The original model has a pop-out carry handle and a recess to stash the keyboard into. All you need then, for here-to-there, is a monitor, cables, and AC.
In Australia the C128D originally sold for $980AU (1985-6).
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"The C128D"
C128D Internals
"The C128"
The US version C128DCR lacked the transportability-features. C128D models feature
THREE CPUs: CSG 8502, Z-80, and 6502. That last one is for the 1751 drive!