Gimme a while to come up with something cool to get a big "high dollar" bank. In the meantime...
Target a bank in a smaller town, less law enforcement, less trained and experienced law enforcement. It's an advantage, though only slight. Get say 4 guys for the team. One driver, 3 robbers. Getaway car is something decently cheap but a rwd sedan, ie older M5(the one with the V8, is it E39?), make sure it's in good running order, everything ready for hard driving. Downside to M5 is that it doesnt blend in well. Leave it up to you to decide your car. Obtain 3 menacing looking firearms. I would say UMP 45's, but those are hard to come by and my plan involves no actual shooting so useless power. 3 shotguns will work. Black and all the same. Dress in all black, all wearing masks of course, gloves, everything. All the shotguns should be the same. This uniformity will create a professional look and cause more fear than billy bob walking in with his hunt'n gun.
The robbery. Burst through front doors, get everyone on ground, watch for texting, calls, have one robber instantly rush and jump over the counter if possible and order all tellers back. Have all cash in registers thrown into bag of choice, gtfo. Don't fuck with the vault, don't shoot anyone. If you go down, you go down as a small timer.
"When the fear of death outweighs the thrill of speed, brake"
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