The chrome or black chrome "C" lenses can be found very cheaply on Clubsnap sometimes, esp the 150mm Sonnar. They may not have the T* coating (so contrast may not be as high in some situations), but the optical configuration remains the same as the latest CFi/CFE lenses for many of the classic lens designs. You should note though, that the "C" lenses are using the decades old Compur shutters which are no longer made, so new parts are not available. But good repairmen will be able to salvage parts from other damaged lenses, so "C" lenses may be a good alternative if you're on a tight budget.
The "CB" range of lenses are part of the new generation lenses, but made to fit a smaller budget than the CFi/CFE. I've not used them personally, but people online claim that the 160mm and 80mm are not as good as the CFi/CFE. Not sure if its consumer psychology at work, but I'm sure that the results are very good even if it's not stellar.
The CF/CFi/CFE versions have the latest optical formula lenses (such as the Sonnar 180mm), the best internal flocking, the latest shutter etc. You can sometimes find very good deals on them, although they are rarer to come by. I do like the "C" lenses' way of locking the shutterspeed and aperture for constant EV, but with the newer lenses you must press a button to lock them temporarily (which is more clumsy I feel).
Nonetheless, for any of the lenses regardless of the version, check the shutter speeds esp the slower ones. There are two gears for mechanical shutters, and the slower one is usually used less and tends to gum up. As usual, check for fungus and lens element separation (esp for old lenses). Check that the aperture and shutter blades open up and are equal on all sides (otherwise it's sign of shoddy repair and will affect your images). Note that for some lenses, the shutter blades do NOT open up completely. There are like 5% of the blade tips which can still be seen when viewing through the lens, which the authorized serviceman from Hasselblad told me is OK. So don't get too worried if you see that! Check that the PC flash sync post is working (otherwise you can't fire a flash) and that the post is not loose. Finally, check for any scratches on the lens elements especially on the back element (cuz sometimes the lens jams and some hamfisted photographer may scratch the rear element when trying to free the lens from the back of the camera.
There... sounds dangerous buying a used Hasselblad Zeiss lens? Don't worry... it's not! Just follow the instructions!
