|Floor area :||2719.58 sqft|
I reproduced an actually existing house because the house looks fun to live. It has a spiral staircase, step-down floor, and loft of the child's room.
You can compare the above snapshots with some photos of the house in the following website.
The house: https://www.onodera-koumuten.com/cms/portfolio/913
[Note] Some part of the house is my guess since there is no photo.