Right now FC houses are considered "private" to be used by FC members only just like there's private houses to be used by individuals not part of an FC. I suggest merging these idea's:

- Both FC's would be able to click the vault in the house "but" they would only see the vault/content that is tied to their own FC. So they won't be able to touch yours.

- Both FC's would be able to use the NPC's & retainers, chocobo stables by default but you would need additional permission for the gardening plots, workshop, item placement, fc actions or food buff usage in the house.

-In this situation you would only see your own Free company chat by default so you would still need to idle in garden and talk to people "in person" or through discord if you needed help from the other group, respecting their privacy in game at all times and avoiding drama (in case both communities do not get along in game in terms of attitude).