Look for a friendly Ghoul named Edward Deegan. To trigger this quest, head to Diamond Market and enter the Dugout Inn. How do I start the secret of Cabot House? If you were kind to him throughout the mission, he will tell you to come back in a week.
If you kill Lorenzo, which you do by flipping the four switches on the walls, you head back to Cabot House with Jack where he give you about 500 caps. This is actually just a gun, but its pretty cool. The reward for killing him is the control of his “artifact”. If you don’t have much need for the serum then this is the option you should go for when faced with the decision to kill or free Lorenzo Cabot. Killing Lorenzo is the morally sound choice to go with.
