"Fantasy castle sketch 2 of 3" by DaveyBaker (resized) is licensed under CC BY-NC-ND 3.0
The title of this book is a little misleading – this is not just a book about strongholds and huge, sprawling estates owned by epic level accountants. The Stronghold Builder's Guidebook can be of use to any DM for just about any kind of group, and it has value for players, as well. The Guide outlines all sorts of buildings for you – what's in them, what it costs to own them, and what it costs to hire staff. The book goes beyond the house prices listed in the DMG by letting you customize your world outside and inside, whether you're playing traditional D&D or D20 Modern.
The Stronghold Builder's Guidebook starts by outlining a process for creating buildings. This process has a decent number of steps but it ends up being easy enough to follow. The book also refers to different types of building materials, spells that can be used for construction, and wonderous architecture for the truly wealthy. I've found the most valuable part of the book to be the components section, where different rooms are described and priced. Armed with such fine descriptions, players and DMs can envision shops, churches, and taverns in depth. The same descriptions also make it easier for DMs to alter rooms if they don't quite fit the milieu of the current game. A barracks can just as easily be built in a house or a ship, and the alchemical laboratory can stand in for a mad scientist's lab in a futuristic campaign. The Guide then becomes a resource that can be used for many different d20 games (and it can at least provide inspiration for non-d20 systems).
But the best thing about the rooms section is that it breaks down even the largest buildings into their component parts. This allows buyers to choose individual rooms and leave out superfluous things so that they can build grandly or modestly, on a large budget or a small one. A character doesn't have to be 15th level to afford a house of their own; NPCs and player characters can invest in places the group will enjoy returning to. The DM can use the rules to determine what sort of house a bad guy has and then use it for encounters, instead of a traditional dungeon. Players can also take part and invest in different buildings, which they just might need. A player character who takes Leadership might find themselves wanting a place for their followers to congregate, and a house easily becomes a home base for characters to work out of. A cleric or paladin might want to raise a church, a rogue might want a thieves' guild, or a wizard might aim to start a college - and the Guide can tell you how much those things will cost. These same locations can become sets for recurring scenes, places of information, and havens for introducing plot hooks.
I will admit that the Stronghold Builder's Guidebook isn't without problems. There are a few errors that might have been fixed in errata, but these errors can be easily fixed by the DM. The book also has a bias toward large and expensive structures; the rooms are described in larger and pricier terms by default. The smallest kitchen, for example, can feed up to fifteen people, whether fifteen people need to be fed or not. But do a little division of price, size and capacity, and voila! You have kitchens that will feed five people or however many you want. Alterations will be necessary for lower-level player characters and they might be required to fit particular concepts, like futuristic or naval designs.
In my games, we've used this book quite a bit. All of my regular players have used it to create homes and businesses for their characters, and a couple of them have even built temples to their gods. The setting is more realized and engaging when the players are able to make their own places in it.
There's a Dragon magazine issue that adds several other components to go along with the Stronghold Builder's Guidebook. The issue is #295 from May 2002 (Vol. XXVIII, Number 12). I happen to like the components they added, like the kennel and the game room (in case your player characters want to run a gambling joint). I also don't mind the strongholds they created as examples, with full descriptions and maps. The map tiles that they included as a pull-out poster are great visual aids for your players, especially if you can't draw or don't have the time to. If you do have a little time and perhaps a mapping program, you can use the room descriptions to lay them out visually, as I did below.
Alchemist lab, created with Arkenforge
This is a rendering of the fancy alchemical laboratory from the Stronghold Builder's Guidebook. Since up to four people can use this lab, it has four tables strewn with materials and four basins of water. The large fireplace serves everyone, as does a chest for the most precious creations. I used bookshelves along one wall because I couldn't find blackboards among the objects I have in Arkenforge, but they work fine. Each larger square represents 2.5 feet. The floor is tile and the walls are stone, just in case. This room could be a part of a castle but it could be attached to just a few other rooms in a simple shop.
Finally, it's worth saying that I did end up adjusting prices, sizes, and other elements from the guide to serve my players. You can see what I changed and why here.
Together, I've found these resources to be very useful and fun for myself and my players. Give them a chance, use them a little, and you'll probably be glad you did.
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