Old Man Stockton laid the foundations, but Bunker Hill can be so much more than simply a caravan stopover.  Using the still-sturdy monument for support, enterprising settlers will make sure that their wares are literally head-and-shoulders above the rest!   This trade and entertainment hub supports 24 employed settlers, and includes beds for up to 30 to cover all the NPC Caravan Workers that come with the location.  Caravan from L0, but will need to import extra food, water and power at higher levels.

The Bunker Hill settlement site in FO4 is a great location, but very constrained by its pre-existing walls and buildings that cannot be scrapped, plus NPC's that cannot be moved or assigned to tasks (but still require food and beds).  With this in mind, the Skymall city plan uses the monument as the core of a vertical complex of homes, shops and recreation venues to drive the beating economic heart of Boston and produce a steady stream of caps.  From upgrades to the existing bar, tailored boardwalks to keep your boots free of mud, vastly improved latrines (I swear we lost more people to tetanus than raiders with the old ones...) and gorgeous high-rise views of the area while relaxing, the Skymall provides everything a caravan worker (or wandering Vault survivor) could want in a stopover.  Unusual shops sell items that can be hard to find elsewhere, and carefully augmented defenses mean you won't have to worry about a super mutant interrupting your dinner.

Choosing this plan will let you watch the settlers build for the sky as they also make modest improvements on the ground.  Even Old Man Stockton's original caravan trading area receives some love, with extra lighting, decorations, and a roof that finally keeps out more rain than it lets in!  This is intended as a mid-to-late-game plan, and will rely on imported power as well as food and water to thrive.   Some minimal industry is present, but caravan connections from L0 onwards ensure that the Bunker Hill Skymall can leverage all the work you've already done to build up quickly and keep its shops stocked.