Hard off is a chain for used hardware in Japan. Keeping some notes here on which stores I visited, and what they had. More categories than single items.. as the items change over time.
Northwest of Tokyo
HARD OFF Oizumigakuen/ハードオフ 大泉学園店
住所地：〒178-0062 東京都練馬区大泉町6-2-5
visit 20231014
this one is quite small. PCs, gaming consoles
West of Tokyo
Hard off Hachioji Horinouchi shop/ハードオフ八王子堀之内店
所在地: 〒192-0355 東京都八王子市堀之内3-3-11
visit 20231001
PCs, gaming consoles, MSDOS floppy games, 8inch floppy drive, NEC PC 8801-MK2, NEC 9801VM, NEC PC8801
Hard off Hobby off Off House/ハードオフ多摩和田店
所在地 〒206-0001 東京都多摩市和田1434-1
visit 20231001
PCs, model railway cars, NEC PC-8801
HARD OFF Inagi Yanoguchi Shop/ハードオフ稲城矢野口店
visit 20231001
HARD OFF KICHIJOJI/吉祥寺店
visit 20231014, 20240211
rather big
PCs, gaming consoles, some old pcs, many instruments and much audio equipment
Hard Off Mitaka Jindaiji Store/ハードオフ三鷹深大寺店
visit 20240211
PCs, gaming consoles, MSX (as of 20240211)
Hard Off/ハードオフ 高円寺純情商店街店
visit 20240212
rather small, just few PCs, gaming consoles, instruments