Brett is one of the few merchants who sell large quantities of rare .44 ammunition.
If the player character has already wiped out the gangs in Nuka-World, they can speak with Brett about it. In appreciation, Brett offers both a discount on merchandise and the key to his safe.[5]
↑The Sole Survivor: "You and your family live alone out here?" Brett Dunmore: "That's right. Don't get any ideas-- Monique and I were Gunners, back in the day. We can handle ourselves better than most." (Brett Dunmore's dialogue)
↑The Sole Survivor: "I wiped out the gangs up in Nuka-World. Should be a lot safer around here now." Brett Dunmore: "Ain't that something. Well, you've done us quite the favor. Tell you what... I'll give you a discount on everything I got. And... take this. A while back, I stashed a safe up in the hills, west of here, at the base of the big cliff. You want anything, take it. It's all yours." (Brett Dunmore's dialogue)