So, I thought this was inaccurate for awhile. Did a little research and turns out setting "Guild Member" access for items and storage containers in player-owned homes should be... well... more accessible.
If you scroll down this page to where it talks about "Item Security" and setting access, it states:
"Guild Members – this option only appears if the house owner is in a guild. Any character who is in the same guild as the house owner named on the house sign, even if not friended to the house, will have access provided that character holds a rank of Member or above in the guild. Ronins will not have access, even if friended to the house."
What this means is that ANY character who is in a guild should be able to set items or storage containers in their home to "Guild Member" access. Currently on Heritage, I believe that privilege is reserved only for guild leaders who are also the owner of that home (not verified.)
As you can see, I am in my Luna home and trying to set the access on a chest. I am not given the option to set access to "Guild Member," despite the fact that I am in Empire of Zeal (and an emissary, no less!)

Please make this change, as right now trying to run a guild without it is a huge pain!
If you scroll down this page to where it talks about "Item Security" and setting access, it states:
"Guild Members – this option only appears if the house owner is in a guild. Any character who is in the same guild as the house owner named on the house sign, even if not friended to the house, will have access provided that character holds a rank of Member or above in the guild. Ronins will not have access, even if friended to the house."
What this means is that ANY character who is in a guild should be able to set items or storage containers in their home to "Guild Member" access. Currently on Heritage, I believe that privilege is reserved only for guild leaders who are also the owner of that home (not verified.)
As you can see, I am in my Luna home and trying to set the access on a chest. I am not given the option to set access to "Guild Member," despite the fact that I am in Empire of Zeal (and an emissary, no less!)

Please make this change, as right now trying to run a guild without it is a huge pain!