After July 1, 1994, manufactured, modular, and mobile homes placed on sites located outside of mobile home parks shall be placed on a permanent foundation system. A pier footing system, where the manufactured home is supported at key structural points as opposed to a full perimeter system is considered permanent, if constructed according to industry-wide standards and if visually compatible with most nearby residences. All permanent foundation units shall be installed with support and anchorage, with applicable portions of the system extending below the deepest frost line. The outside appearance of every foundation shall be visually compatible with most other permanent foundation systems in the same addition, subdivision, or area of the City.