I honestly don't consider what the value of a record is when I play it, I just play the stuff that I enjoy playing, and enjoy seeing people enjoying what I play.......If a record sounds good and get's spins, people will automatically try to get the record, this creates demand, demand forces the price of a record up, it doesn't mean that it is rare !, I think there is often confusion between what is rare and what is in demand....
I think that in answer to the original question, there is no answer......