Not sure if this can count as an official guide, but it's not actually just a quest post either. So I'm posting it as a guide

This seems to be asked a lot in game, so I thought I would post here about it.
This is the banker's quest to expand your bank space and your inventory space.
Each time you expand your bank space it gains 8 extra slots.
The banker will ask for either materials or a bank enlargement stone. The stone comes from the Item Shop or you can buy it from other players. It looks like this:
Bank Enlargement Stone
Or, you can get him
5 of each type of certain materials for the first expansion:
Materials to get -- 5 of each:
Soft Fur
Phantom Flesh
Evildoer's Mask
Elemental Powder (don't confuse this with Elemental Dust)
Antennae
Ivory HornOr give him an
1 Enlargement StoneThe second time you do his quest, he'll ask for
10 of each type of material.
Materials to get-- 10 of each:
Phantom Claws
Leather Bag
Elemental Fragments
Blunt Claws
Glade Dew
Honeydew (don't confuse this with the Nectar you can harvest)Or give him an
1 Enlargement StoneAfter doing the quest with the materials, he'll only request an
Enlargement Stone from you.
The items for he requests are drops from monsters all around. So, if you get any of these in your adventures, save them if you plan on expanding your bank space. And trust me, it comes in handy lol.
Also, he has a quest that you can expand your inventory space as well. I've never done this quest as I'm usually going back and forth to town to turn in quests and haven't seen the need to expand my inventory.
But, he'll ask for
1 Inventory Enlargement Stone which is also available from the Item Shop or from other players. It looks like this:
Inventory Enlargement Stone
**Note: When the MY-EN version comes out and the names of items are changed, I'll edit this guide accordingly, so don't worry.**

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