My absolute favorite and best way to do it is the Big Con . Although others might say silent and sneaky is better I think not . With the big con if you do the gruppe sechs disguises ,you immediately get access to the vault you don't need to avoid or knock out anybody when entering the vault area .
Those are: casino model, door security and vault door. So my question is, I've to buy them er'time I do the heist or is one time buy and I'll have it in every set up I do?