Many residential and commercial building tenants would like to have inexpensive, rent/property tax, free utilities, travel without leaving their residences (i.e. yacht, houseboat, etc.), and protection from floods.
Additionally, in the distant future, Earth may experience rising water levels, another deluge, etc. RA, in this event, would last far longer as a habitat than land anchored structures. A residence that could both float, and execute controlled underwater submerging, would be ideal.