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.
A far more interesting question is "Does he actually sell anything at those wildly inflated prices?". Case in point, he's trying to sell what looks to be the English language version of Metal Gear Solid 2 Substance for over $300 at current exchange rates and ~$180 for Knight Rider & Knight Rider 2 (the two games by Davilex).
You have to think he operates and sells things internally (to be honest you are not supposed to sell things abroad in japan, dunno if it's a government law or something else). So for them an american or euro version is considered exotic and pricey but yeah, those prices you mentioned are absurd.
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