IIRC the commercial VP machines have at least two chambers.
One is where the Galden is heated and stored (lower part) and the other is where the boards are placed and removed.
So you place the boards, the top lid of the top chamber is locked, the under lid is retracted and the boards lowered to the height where the damp is.
Then they higher the boards , close off the hot Galden reservoir and then actively cool the upper chamber walls with an AC unit and small fan forcing the low amount of escaped Galden damp back in liquid state.
After a time period the fan stops, the top lid opens so the boards can be removed.
The (escaped) liquid Galden remains on the lid where it can be left without evaporating, next cycle it is drained back into the hot Galden reservoir when the cover re-opens. Something like that, was shown to me somewhere in 2004 I believe, and indeed without the AC unit it could be build for a couple of hundred $, which would be the price you could buy them for if two million people in the world wanted one.
The rest of the price at this moment is that they are is not mass produced machines and you need a ROI.
I always compare it to the sous vide machines, those can heat a waterbasin to 0,1oC from 30-100oC and those were ten years ago all over $2000. I build one myself. Today you can buy them everywhere for $300 and even the small standalone heaters you can put in any pan costs <$90.