I modeled everything except some small props on the train that are from some free greeble packs from ‘spacehead’ on Blend Swap and the character clothes are from Sketchfab (Hoodie by Virtual Pandora, Pants by Dubel and Boots by KIFIR).
I made a video on this project, explaining my process and answering some questions from Reddit about achieving a sense of massive scale, texturing workflow etc. You can check it out here:
As mentioned in the post, I modeled everything except a few small props on the train/rooftops and the character clothes. I show in more details in the youtube video breakdown linked above