I suggest the option for dungeons equipments to be sell back to vendor for the same dungeon tokens.
Maybe implement a small fee, it could be return 5silvers to return per item, or simply getting back only 80-90% of the tokens spent for that equipment.
It allows the flexibility between different builds and characters without needing to grind the same dungeon to get a different piece.
Of course if you want an extra piece of equipment for use or something from another dungeon, then you have to run dungeons again.