I recently purchased a Contax IIIa from a woman I know from work. It came with the Carl Zeiss Jenna Sonnar 50mm f1:2 T, Zeiss Opton Sonnar 135mm f4 T, and a 3.5-13.5 viewer. I paid $150 and see online the cameras are not going for much more. However I’m constantly seeing prices for the Contarex Bullseye of $1000. What makes the Contarex so much more valuable? I’m ending up being a bit of a camera collector when I can find them free or for a few hundred at most. I’m finding I’m partial to Carl Zeiss lenses. My first experience with these lenses was on my Fathers Rollieflex T that has a Tessar and another I purchased with a Planar. now I have the Sonnar. I thought it would be fun and economical to own a few cameras in which I could use the same lenses. Hence my interest in the Contarex. I’m also interested in a Contax RTS but I’m not sure if my Contax lens will work.