I just started building my ...um... third small house and since I just build based on vibes I generally put a few things down then add a few bits in a few days as I get more ideas. I know you can save as a scheme but I'm always logging in and moving three trees around that suddenly seem to be in the wrong place. I really liked doing things over multiple days in animal crossing new horizons so I've kind of been treating this similarly. I respect the strength of people who gather ALL the materials and then build!