Buy second hand textbooks – Japanese textbooks
You can buy used Japanese textbooks (nihongo kyokasho) like minna no nihongo in here! Also, fellow foreigners, mostly foreign students studying in Japan sold their second hand Japanese textbooks here. It will be cheaper to buy Japanese textbooks from fellow foreign students.
If you are a foreign student in Japan who took some Japanese classes, you can also sell your textbooks here. You can start selling your used Japanese textbooks by clicking +START SELLING button on the top right.