So I been modeling this tank since February, but I kept stopping and progressing but kept note of when I stopped and when I continued, and it was only 14 days, For background I did it today and only modeled wherever you can see in camera. Workflow for background was simple, you create simple blockings in Maya and sculpt in Zbrush for normal maps, silhouette. Modeling progress was about 15 days total if I did not stop and progress every moment. But yet I'm quite busy with graduation project and job application so I wont be able to do that much of personal project but focus on modeling and compositing. Well, enjoy the artwork