Ah man, that is so awesome seeing those prices. I remember buying most of my figures as a kid. My brother and I would save our allowance, pool our money, and buy everything we could get our hands on, but I couldn't remember for the life of me how much they were. 5 bucks is SOOOOOO cheap, but as a kid I remember it seemed like a big deal.
The one thing I do remember is the Eternia set selling for $99.00 at the Bay (a Canadian department store) and I just about fainted when I saw the price. I wanted it soooo bad, but never got one because it was too expensive. Less than $30 for Grayskull, that is out of this world!!! Battle Ram for $15... OMG!!!!
I love remembering my childhood, which is inseparable from MOTU.