Well I dont personally see why anyone other than an FC would need a mansion and 700 pieces of furniture, but that's the choice you've made.

Im not ok with having to pay money to be inconvenienced, but at the same time, people like yourselves who have over invested in housing are the minority. Setting up an entirely new system of storage for people who cant be accommodated by whats already available is unlikely to happen. In a perfect world it would be great but realistically theres only so much they can do.
Giving more than 3mil would be overkill for the majority, and setting up new storage options would take further resources, snd may not even be possible given the restrictions of the base code.
At most, they could offer a free retainer or two for that month.