The wine cave story makes me think somebody liked how it looked more than how it drove. Very cool conversation piece and likely not the only cool car owned by this owner?
I agree that $30k is high for this particular one but $20k might be reasonable.
I'd think $18-18,5 would be close to right. Buy it for that, go through all the electrics, hydraulics and mechanicals, then Subaruify it for a really nice "resto-mod" of an actually old car.
It has been done.
But if the seller's not motivated, plenty of other fish in the sea—especially at your stated budget.
Good luck with your search, RayRay.