Yeah right, some of them are objectively very rare but the prices are imho out of this world for a lot of them (over 100$ for some loose games without box) and many prices are random-ish.
https://auctions.yahoo.co.jp/seller/lets_goda2001
This bastard buys games at low price on surugaya and re-sells them on yahoo
People like him kill the collector world imho
Collecting games has become more and more hard job nowadays