Rare soul can also have the meaning of sounds you hear rarely, if that makes sense.
There was a time when it was public knowledge IF a 'big' find took place in a warehouse in the US where all of a sudden 100 copies of a hard to find record had come to light, but I cant see that happening now or even in the last ten years.
It has been known that a dealer found a hundred copies of a great sound, got DJs to break it in and then release 2 or 3 copies a month, so they could get the best price etc.
A good example is the Ringleaders - Baby What, etc - Mpac.
£30 a copy for months back in about 79, then bam its a £1 record when all those who could afford a weeks wages had bought one.
The dark side is alive and well on the scene. Buy with caution.
Ed