Me and some friends have created a small guild to make it easier for us to trade things which the others may need or to share crafting materials. But then we saw that one only unlocks the guild bank by having 10 accounts in the Guild not 10 characters as we previously thought, the game doesn't seem to care that we may be only 5 accounts but we play with more that 10 characters. As we don't want to invite potential bank scavengers and also don't want to just trick someone in joining us so that we can use them placeholders, we are looking for a small guild (at least 5 Members) with the same lack-of-members problem, so that we can help out each other.

My Idea would be that we invite each others members to our guilds to fill them up to 10 accounts but both of us restrict access to our respective guild bank for the members of the other guild. This way both would have their guild bank unlocked and didn't have to invite other people.