I've just received and Exakta Varex IIA, given by a member on another forum. It looks to be in almost immaculate condition (although the ground glass needs a dust) and the shutter seems to work. At least, it opens and closes and uncovers the whole frame, so that's a good start.
My first SLR was an EXA IIB, traded in for an Exakta Varex IIB in 1967. I still have it, but the shutter doesn't work and the pentaprism has a rattle which wasn't a built in feature. So I have a camera that is an improvement, and it came with what was the then top standard lens, the 50mm f/2 Pancolar, which I can test on a Sony a7rii.
I have a very soft spot for Exaktas; although NOT a collector, I now have 4, three of which appear to work. The other two are a Kine-Exakta (second model c1938) and a Varex IIA second version c 1957). Fun cameras.