IIRC, Klein used DuPont Imron Paint system on their framesets which eventually ended up non-compliant to modern VOC limits set up by the EPA for paint systems......
I understand that getting a Klein refinished with the same paint systems that was applied in the factory is turning out to be close to impossible these days because of this.....
the special aluminum alloy tubing that Klein used that was so special in their days do not seem to contribute to Klein values as much as they did in the past, as Aluminum frames in general had not been looked at with "kind" eyes in recent years, now being mostly considered as yesterday's technology that has supposedly enough negative characteristics to it (harsh ride and possible propensity to cracking over time) that they usually come behind steel generally, when it comes to C&V values.
In their heyday, Klein was pretty much considered the "rich man's" bike, similar to what Kestrel was. ahead of their time and too expensive for anybody less than a rich doctor or lawyer could afford back then..... A "yuppy's bike" if anything else. But these days, with their depressed values, the regular C&Ver can finally afford a nice Klein frameset and try what only the only the rich cyclists used to be able to afford......