The shapes were simple enough in maya. I just kept it all as low poly as possible, but that also allowed me to have more in the vertical to better capture the curve of the walls as well as the light fixtures.
From there I moved right into working on the materials for the walls and floors.
Similar to the old house exterior, I called out values in the substance that would let me modify the scale and amount of tiles in the floor and walls to more accurately match the reference. However, these materials are much much simpler.
After all of that was done, I did a quick test in Unreal to see how everything was coming along.
My initial reaction would be to brighten up the walls a bit, to help take the load off of the lighting. This will require some back and forth, however.