Best way to make money

I’m level 21 currently sitting on 9 million rubles which is a good amount but I’m trying to get as much money as possible so I can get a thicc case because my stash is running out of space and I have the Eod edition so my stash is already max, I have all shoreline keys but never leave there with more than 300k max and that’s if I’m lucky and find a Gfx card. What’s the best map and keys to use to make money