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seller; vendor
売り手市場では価格が上がりやすい。
In a seller's market, prices tend to rise.
中古市場では売り手と買い手が直接交渉できる。
In the used goods market, sellers and buyers can negotiate directly.
売り手責任として欠陥があれば返金に応じる義務がある。
As seller responsibility, there is an obligation to offer a refund if there is a defect.