"Koni-Omega 6x7 rangefinders are very inexpensive, with excellent lenses. They are heavy and prone to frame spacing problems, but usually that only affects a bit at the edge of some negatives on the roll."
I'll second this suggestion. the whole camera system is quite inexpensive for what you get. The four lenses are incredible. They should be, as Konica copied the designs of only the best: Super Angulon (58mm), Tessar (90mm), Sonnar (135mm, and Tele-Xenar (180mm). These cameras were expensive when new and used heavily. The film backs can develop frame spacing issues, although I own (and owned) many and never ran into the problem. Repair requires a CLA of the back, but the mechanism is surprisingly complex and best left to the experts, who are around still. The 135mm is extremely rare and thus very expensive; best to go with the 3 lens kit. Of the many variations, I prefer the Rapid Omega M, or Rapid M, which have mid-roll interchangeable film backs and predate the later period when Mamiya took over manufacture of the bodies. They are heavy, but have very ergonomic design and control layout.
