My name is Alexander Kolyasa. Currently I'm working as middle 3d artist in Plarium. In my video I will show you my workflow of creation game props.

Main point is that you can model middle poly and then in semi-automatic way convert it to high poly and also very easily reduce it to the low poly. I use a lot of this technic, especialy in hardsurface modeling. 

Link to my artstation https://www.artstation.com/ask 

Software- Cinema 4d, Zbrush, Photoshop+Quixel Suite

Reference: www.environment-textures.com