The car hesitates slightly when accelerated. I believe it's the accelerator pump inside the carburetor.
This car rides as smooth as I have ever seen a car ride, even being 32 years old.
The body on this vehicle was put together with some extra strong something, because it has no squeaks whatsoever.
It is a German model with German specifications, so it has no air conditioning.
I wish I could find an AC kit for it, but I don't want to kill the value of it.
If you like it that much, and air conditioning would make you happy, just go for it. As good as the car is, it is also something which has to serve your needs. I doubt it would depreciate the car that much. In many other countries, aftermarket air conditioners were installed on many cars, even very expensive ones, simply because they were costly options from the factory.