My builder uses Houzz Pro to plan the timeline and give detailed estimates and daily updates with photos of progress, and provide invoices at pre-agreed key points in the build. This made the whole experience much more efficient and stress-free.
The rug is actually carpet squares (that can also be cut into diagonals). They come in 19.7" squares and can be put together in any configuration. They also have many different colors and patterns. They are from Flor.com but other companies also have something similar.
Mary Anne Smiley Interiors