The RT-Crew's minimum system requirement is to have at least 16GB of physical RAM (more is STRONGLY RECOMMENDED) to minimize crashing from insufficient memory.
Really took my time grinding up those c-bills, got me an Awesome, Highlander, Annihilator, and a King Crab (all vanilla, mods for weapons/gear). Running 3.5 and 4 star missions hasn't been nearly as scary as I thought it would be. First time diving into HBS Battletech (with very few mods).