All the itens items groupable I send to stash. This way I basically DP to save equipments, equipment, quest itens, items, and general stuff.
I let each box for an specific Npc that buy it, for example:
Box1: rashid Rashid items
Box2: blue djin itens
djinn items
Box:3 green djin djinn items ....
Inside each box u can use backpacks to separate every item or just put all together (I use to let all together considering all will be sold at the same npc).