A 100% or “all cars unlocked” save file typically provides:
: Many community-shared save files include "My Cars" slots filled with police cruisers, transport trucks, and even Mia’s Mazda RX-8.
: If the game says "Unable to load," ensure you haven't renamed the file inside the folder; it must match the folder name. Black Screen
This article covers everything you need to know: why you would want a completed save file, where to find a safe one, how to install it correctly on modern systems, and the potential risks involved.