Here is my model from the extruding challenge applied with multiple materials on this challenge. It’s actually more than 1 objects because I had to copy the roof shape (coz I’m lazy to model it 1by1) but the building itself is only one object that was made from extruding the default cube ;3
ref:
Multiple materials does helps a lot!
Fine job. Duplication is core to modelling no harm in using it. Yes colours make a big difference and full materials even more, that will come later in the course.
You missed the windows above and beside the entrance, from your reference!
Is a good thing! Because it makes it easy to reuse the building with a flat roof. In that way, you create a city with different buildings in no time.
Thank you!! can’t wait to learn full materials
wise one said “copy, then change a bit” 
lol jk
Aaaah I see, that made so much sense! no way on earth I would model same thing hundreds time
That’s really great! I’m inspired by your work. 
