The shop has a main counter in the center, manned solely by Arturo Rodriguez. Behind him are several ammo boxes, a weapons duffle bag and the door to his house. To the right is a weapons workbench which the Sole Survivor can use to modify their weapons.
Arturo has a multi-level house. Depending on the time of day, the Sole Survivor can sneak in, or the door may be open.
Commonwealth Weaponry is mentioned as a sponsor for Diamond City Radio.
Commonwealth Weaponry only appears in Fallout 4.