This is a mansion of a home in anyone’s book
Charis is a big home in anyone's book, 3,000 sq ft, and while it might be relatively easy to spend heavily on extra finishes in a regular sized residence, it takes a bit more nerve and depth of pocket in a place this size.
That 3,000 sq ft is spread over ground and first floor level factor in a floored attic area with two Veluxs to the back, with folding stair access only at present, and there's 500 sq ft more to colonise.