C:\Program Files (x86)\Steam\steamapps\common\Cyberpunk 2077\bin\x64
GOG
C:\Program Files (x86)\GOG Galaxy\Games\Cyberpunk 2077\bin\x64
.../AppData/Roaming/REDModding/WolvenKit/MaterialDepot
, however any custom folder can be substituted. A Depot with materials can be in excess of 30 gigabytes, so we recommend a destination with ample free disk space.