The value of anything is based on what someone is willing to pay at any given time.
I have seen fluctuations on certain chips here go from one extreme to another.

Let's say for arguments sake that you and I get in a bidding war because we both wanted a particular chip and it sells for an exhorbitant amount. Does that really indicate a realistic value? I think not.

I think factors like present supply, demand or nature of the economy have much more of a bearing.
Take a look for example at the HR Pink Taco chip or for that matter almost any HR chip see what they bring today vs. only 2 years ago.

I think I have said this before so for the sake of repeating myself, I never viewed collecting chips as an investment.
I can think of a multitude of things that make much better investments, to me this is a hobby I enjoy exactly for that purpose, a hobby