I think that a guild should be able to summon a guild castle with a safe house where you can deposit or withdraw resources. You could sent troops to the castle to protect them. I know your thinking that there's no downside to this and it's true. That is why I think your guild castle has 5 lives. It falls five times;and the guild is disbanded. The castle cannot be moved unless the leader and at least 50% of the r4s agree.