Quoted from Blackbeard:

The way to figure out a good price:
Take the average of this:
Price an owner thinks his PIN X is worth and the price a prospective buyer thinks PIN X is worth.

Quoted from Rarehero:

Your "I won't pay more than..." just keeps inching up and you get less anxious. I started with arcade games, and never paid more than $300...most of them were $50, $100, etc. My first pin, BTTF, was $300 - that's how I got in! It was within my self imposed limit. My first "big" purchase was a BSD for $1000. I couldn't believe it - I thought I was insane. Then my ceiling kept inching up...$2300 for RFM. Most of my purchases were $1-2k, sometimes less...and I could always sell them for more than I had into them. That finally got rid of the anxiety. I finally hit $4k when I bought CV. I felt really weird doing it, but it was done. Then I finally got into NIB territory and it's all over. LOL