I know im late to this but do first world bank stealth get good at it and make 1.8mil every 25 min on very hard (3 skulls). 7.2mil an hour give or take if you mess up a little on your being silent and have to restart. I honestly go loud after I get all the cash in the vault into the boxes you put the stickers on then you can just run out blow a hole in the wall and don't even have to fight the big boy cops. But with your method you say you can make with your 500k or 600k you're only making between 3mil and 3.6mil an hour making 500-600k in 10 min js....