And I've only found maybe 2 magazines for unlocking additional buildings/extras to create from your workstation, so feel free to give better advice if you have more unlocked.
If you plan on really building a nation of settlements, there are really four things that I find critical to create in each settlement:
1. General Store Emporiums - You can buy a ton of junk at these stands that have a lot of rare components (fiber optics, gears, nuclear materials, ceramic, crystals, etc.) This saves me hours of running around the wasteland trying to scavenge this stuff. If you don't have the perk unlocked for the emporium, at least build the highest level general store you can.
2. Gun Store Emporiums - Ammo, ammo, ammo. I always found myself really low on .45 and fusion cells until I started building these in several of my settlements.
3. Build as many water purifiers as possible, I earn 8000-12000 caps a trip every time I come back to check Sanctuary. (posted by Battlebloodmage)
4. Scavenger Stations - One in every settlement. Its not so much finding rare junk as it is gathering a lot of resources/materials. The more idle survivors the more resources will randomly be scavenged.
I have 20 settlements right now and all of them have at least two stores (general/medical/restaurant/armor/etc.) and one scavenger station in each settlement. Having this many stores throughout my settlements, I am raking in thousands of caps each day for doing absolutely nothing. This constant flow of income gives me plenty of cash to buy all of those rare junk items to break down for much needed components and ammo. Its a wonderful cycle that runs itself.
Obviously you need supply lines connected to each one and plenty of food/water/defense/beds to maintain a high population.
If anyone has anything else to add, as far as their ingredients to building settlements, feel free to post them.
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Additional and very useful, in-depth tips provided by Gamefever:
Building Tips,
Use Foundations, Concrete Platform and stilted platform to create level surfaces for building
-Do not build another floor directly over these platforms if you can, causes navigation issues for NPC's
-Best to build a ring with these
-Pressing and Holding the Activate key on a foundation piece grabs all pieces connected to it and can allow clipping into buildings, the ground, and many other objects like trees.
-You can stack Concrete Foundations to create sizable walls or even concrete structures.
-If you build your foundation high enough over dirt and allow an access point, plants don't need sunlight.
Scrapping Weapons and Armor while in the Build Function gives additional build limit.
Bunkers
-One settler can man 3 bunkers and gives a score of 6 defense rather than just 2 when done this way
-Bunkers can be clipped into structure walls by using a floor rug, allowing for the bunkers to be worked into the structure in a more convincing way.
-This helps with noise because consoles cant use mods to reduce turret sound level yet.
Resource Links
-A settlement does not have to produce food and water, if a provisioner links the settlement to a settlement that produces enough for both.
->This means the chance of this location getting attacked is very low due to no food or water here.
-Provides access to resources in Workbenches and Settlement Build Menu
-Can see which settlements have links in Map Menu of Pipboy
-Can Link 6 Settlements
-Distance appears to be an issue
-Best to link all settlements to a central zone
-When making a new settlement consider sending its 1st settler to a resource depoy like Sanctuary rather than send one of Sanctuaries Settlers to provide for new settlement.
Collecting Resources
-Stuff accumulates faster if you empty the bench of that item.
-Place a container right next to your Workbench for ease of transfer
-Place Shops nearby a Workbench for ease of Selling stuff like Water or Produce.
-Diamond City shops restock every 24 hours, you can buy 100 wood from Baseball vender guy.
-Abernathy Farm sells 50 wood dailey
>there is a location near Abernanthy with decent amount of lootable objects for building
-Every 7 days world loot respawns
Vendors
-Stock refreshes 24 hour cycle
-Open from 8 Am to 8 Pm
-Bar, produces the most happiness
>Causes all non-guards to meet at Bar location 6am-8am and 8pm-11pm
>All non-assigned settlers hang around Bar's
>Bars generate a lot of Caps
>Bar has a big radial hang out space
>Settlers will sit in chairs and use animation objects in this space even workbenches like Food Stations
Beds
-Settlers must be able to navigate unobstructed to their bed in a settlement
-Best bed for this purpose is the sleeping bag
>Failure to place beds correctly causes "Sleep in Shifts Issues"
Sanctuary
-Has several Spawn Points in its borders
>Best spot to build on is over by the playground equipment next to River
-Easily can place many Water Purifiers here and a sizable farm
-You can place quite a few generators in a Prebuilt house and then run wires with Poles to where ever you need electricity, this helps reduce noise issues.
-Make your main sleeping quarters far away from the Workbench to avoid "hammering noises"
Dockside Inn
-Can place 4 or 5 large water purifiers here
-1/3 of the buildable space is over water
-Foundations placed in Water wont reach the bottom but are convincing enough for looks
-You cannot purchase stuff from a vendor that is placed over water
-most spawns happen outside of its border except raiders which spawn just to the right of the front entrance and can get stuck under platforms in the water if you place a dock off to that side.
>Stuck Raiders eventually drown haha
-Can build high enough to snipe many different spawn locations from here
Defenses
-1 settler can man 3 bunkers
-Spotlights help direct turret fire
>Spotlights are helpful at night for actually seeing things when they work, derp helps player see stuff.
-Construction Lamp is very helpful for player but doesn't contribute to defense
-Turrets
>Height increases range
>has a Field of View
>Can rotate to fire on targets out of FOV if it knows target is there, Spotlights help a lot with this.
>Elevated is best due to Close Combat spawns and Super Mutant Suicide guy
-Defense needs to equal at least the combined amount of Food and Water Produced or you can expect more quests at this location.
>Defense helps reduce probability of attacks occuring
Pipboy,
-You can check status of settlements here
-If you see that a settlement reads not enough beds even though you placed enough than your beds are not actually accessable to your settlers, the pipboy tells you actually how many beds are being used.
>Settlers wont try to use a better properly placed bed when it is placed if the offending bed they are assigned to is still present.
>Sleeping Bags are the easy to place in this regard.
-Happiness issues in Pipboy are a sign that some resource is not being used properly most likely the settlers cant get to their bed or do not generate enough food or water.
-Venders help keep happiness steady.
Settler
-Will use any item you give them
>Aid items, drugs, stimpacks, steathboys, all of it
-Can use any Weapon forever as long as they have 1 bullet for the weapon, yes they can use Fat Mans.
-Seem to be only killable by the player for now *I've notice a few settlers dead on the ground after mutant attacks, I was nowhere near them when they died, so I be careful. I had the ghoul vault seller die from an attack in sanctuary, so make sure you save often and pay attention.
-Don't shoot them ><
-Can use power armor but eventually will get out of it to use their bed unless they are a guard
-Will access any normal container that has a weapon with ammo when the settlement is attacked even bodies, this is why they have weapons and armor that you didn't give them.
-Will use Power Armor that has a fusion core in it especially if the settlement is under attack
-Are said to use Food and Water from workbench when needed, though I haven't confirmed this.
Junk Objects as Decor
-Toss your Junk, Aid item, weapon, armor, whatever on the ground
>Start Build Interface
>Now use Activate Key
>Object will orientate properly and allow placement on say a Shelf or TableTop
>Much easier than doing it the other way.
>>>Can create nice neat rows of Nuka Cola Quantums this way.