If the "Hanks Effect" was really so prominent, then we should see the commensurate rise in price of 5 Series Smith Coronas and particularly the Clipper and the Silent which he's also mentioned several times. In fact, he's said these would be the typewriter he'd keep if he had to get rid of all others. Given this fact, it has to be, in part, a variety of other factors which inflates the prices.

Personally I think that it's a combination of the fact that they were manufactured at the peak of typewriter use and manufacturing and before companies began using more plastic and cheaper manufacturing methods, but were also done in a later timeperiod when exterior design and color were on the rise as a differentiator in the marketplace. Quality, form, and function become part of a trifecta which drive desire and collectability.

Hermes 3000