I need 3 more million so I can get the final two pieces of the uncharted map. Is there any really good ways to make money? I've done a lot of quest today and games.. Can't thing of anything else..

You can buy a 100 Credit Gift Card directly from the cash shop. :)

I make most of my money from quests and restocking. If you're careful which quests you accept you can make a good deal just from those.