For my story, I wanted the main villain, a gang leader, to have collateral on his fellow gang members in case any one of them turns on him. The whole, 'if you betray me, you are going down with me' scenario. However, let's say the leader has collateral on his fellow members, that he has arranged to go to the police, should they betray him. Where would this collateral be kept in such a situation? Would he have evidence on all of his fellow gang members, all hidden in the same place, or would he keep each collateral on each member, each in individual places?