Hello, I am Dmitriy,
Your job attracted my attention because it is compatible with my freelancing interests and experience.
You should know what many designers use third party plugins in 3d max for render, you can't render without them installed, and can't see materials with texture, they can be in black because missing materials from third party render. Often it is necessary to alter the materials for their own use to render beautifully.
Also designers can work in different version of 3ds max for some reasons. Newer 3ds max can open old max files, but old 3ds max can't open file from saved in newer version.
For better quality you can add drop shadows and better self shadows, glass and reflection, but it will need much more time to render each frame
Cheers