My Summer Holiday 155 Days Building 1M Dollars Water Slide Park into Underground Swimming Pool House

My Summer Holiday 155 Days Building 1M Dollars Water Slide Park into Underground Swimming Pool House

How big is this building?
We separated this building into two parts. The first parts is about the water slide and the swimming pool and the second parts is about the underground house. The first part dimension is 9metres by 12metres and it is 4.5metres depth. The second part, underground house, dimension is 4metres by 4metres and the depth is only 4metres.