Being earlier Sinar cameras, if shopping for one, the main point would be their condition. Really clean ones do turn up. The biggest problem is generally with the bellows. Cameras with the original tapered bellows in excellent condition are hard to find. It's a deluxe bellows really nice to work with. You can easily substitute the later box style 4X5 bellows; but if that is what is installed on the camera, there might be other component substitutions too. Everything might work perfectly well, but any hybrid setup should be clearly identified by the seller; otherwise, there might be some unannounced wear and tear anomalies too. But I wouldn't worry about a missing little level or something minor like that.

Even the clean ones need period maintenance and tuning up the screw tensions etc. That's pretty easy to do once you learn how. But the really old ones came with a kind of viewing glass that was coating frosted, and not actually ground glass. It's dimmer than real ground glass, and likely will have yellowed somewhat over time. So in that case, replacement with Sinar's later actual ground glass or some other quality substitute is recommended.