[...] saying that someone had produced such a site like 5-6 years ago [...]
There was such a Page long ago,
but it has gone.
If you browse through AfterWiki
History, you can still find the Link
for AfterWorld Market (07/2009)
http://wiki.afterworld.ru/index.php?title=Links&oldid=28131[...] hard for the market to establish itself with no history to compare prices with [...]
Without enough Trading (stable
Supply and Demand) the prices
will, even with a history Graph,
allways stay like a Suggestion.
Greetings - Zwarky