Here I used the basic shapes to block out the scene, with no real consideration for topology or poly count etc.
I then Imported the entire scene as an FBX into Unreal, added a bit of light and took a walk around. I soon noticed the things that felt right and listed a bunch of stuff that needed changing.
I'll use this in the future as it helps to get a feel for your scene before committing, helps with scales, and I also found it motivational as you can quickly get an idea of what your finish scene will look like rather than just working on a blank canvas.