I recently acquired a Kodak Retina IIa from a retired Kodak engineer. There's usually quite a few of these cameras popping up but none in the condition I was able to find. The camera looked brand new and had the original leather camera case.
The Retina IIa is very easy to use. The best feature of the camera is that everything is manual. No batteries are needed to run a meter. One downside is that while focusing the lens I sometimes moved the aperture dial. The Retina IIa seems to be more of a camera you would use for deliberate shooting. I found the rangefinder to be a bit tough to focus quickly at the start. I have never shot with a rangefinder before. As I used it more, I was able to be quicker to focus. You will get better results zone focusing.
The Retina IIa is perfect for places like Rochester, NY. You can only go to 1/500 second shutter speed. The camera may not like very bright sunny days unless you use 200 speed film or are able to find some expired 64 speed film.
I tried to shoot in as many conditions as possible. The 50mm f/2 lens seemed to work perfectly in fairly bright and dark conditions as well as in some challenging lighting conditions like the parking garage in the above photo.
I have since shot a few more rolls. Once I process the black and white film I used in the darkroom I will share the results. I think I will enjoy shooting with this camera through the winter.