I have to admit I have never played Caravan in this game, it seemed pretty. of bugs at the bottom of this page: http://fallout.wikia.com/wiki/Caravan_(game). the craps and roulette tables work instead of ♥♥♥♥ing Caravan.
That is the safe method, but with LU 7+ it is more optimal to go around 90-95% of the ban limit, and play roulette, single number only, max bet.
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