Let's dig into the economics of D&D and see what I come up with. This is stream-of-consciousness homebrewing. Unedited. This is what my workflow looks like.
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Average monetary treasure by tier
T1 375.7
T2 4497
T3 36370
T4 337962.5
No PC can afford to take a domain before T3. In T3 they can afford to build estates, businesses, forts, and towers. In T4 they can build abbeys, keeps, small castles, and temples. At no point during their leveling career can a single character amass enough individual wealth to contstruct a palace. Their adventuring career leaves them 160,000gp short. In order to build a palace on their own merits, they MUST continue to adventure at maximum level. Otherwise, they either need to go into debt with some powerful people, or pool the resources of the party. Even once a palace is affordable, its construction time of 1200 days means another 3 years of adventuring before your tired hero can retire to his grand palace.
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Running a business.
A town INN costs 5,000gp to build.
It costs 5 gp to run, base.
On average...
For the first 20 days, it costs 1.5x the base price.
For the next 10 days it costs full base.
For the next 10 days it costs half base, but profits cover the remainder, so you're still making no money.
For the next 20 days you break even.
For the next 20 days, you 1d6x5gp.
For the next 10 days, you earn 2d8x5gp.
For anything over 90 days, you earn 3d10x5gp.
You must pend a minimum of 61 days to even reliably see profits. By then, you will have sunk ~5,225gp into the business alone. To cover your initial investment, you will need to run the business for 97 days more, plus the 60 days of construction time, for a time investment of 157 days, that's also the additional price you'd pay for living a modest lifestyle during that time. A comfortable lifestyle costs double. Covering that takes another 2 days, lifestyle of those days included.
So, in full, to make any real profit from an inn takes a full investment of 5384gp over 159 days. After that, you will have regained all of your losses, and finally earn a living from the business alone. In order to even begin, you already must be above level 10, most likely level 15. you will have bankrupted yourself in order to do this, and could have just kept your money and downtime for some other investment.
So, the only reason to do this is for roleplay purposes.
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New DT Activity: Purchase Property
To purchase an existing structure costs some portion of its construction cost.
Businesses cost 50% their build cost.
Military structures cost 25% pecause they are run at a pure loss and otherwise become ruins.
Religious structures cost 75% because they want to be kept in the faith as long as possible, and they want to discourage cross-faith temple conversion.
Domestic structures vary by property value and structure quality.
Most businesses are about 5000 to build, so they are typically 2500 to buy. That means that, while you might not be able to build your way into a domain through a business before T2, you might be able to BUY your way in. It also means a T4 character could potentially purchase an abandoned palace scale structure at 250,000gp.
Finding a piece of property to purchase is a simple DC per day spent searching, based on the construction cost range you are looking for.
5,000 = DC10
15,000 = DC15
25,000 = DC20
50,000 = DC25
500,000 = DC30
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Domain Rulership
In the situation where a character becomes the figurehead of authority ruling over a piece of land, the following rules are used to determine the expenses of protecting that land per day of rulership. These expenses are charged to you on top of your lifestyle expense.
Per 6-mile hex: The wages of 20 skilled laborers (soldiers &or guards) and 10 unskilled laborers. (That's 42gp per day, or 1 silver and 9 coppers per person in that land)
The player can tax his people however he likes in order to cover these costs. It is up to the DM to determine how the NPCs respond to their taxation conditions.
Additionally, the player can choose to under-staff, leaving his domain weak to potential attack. This is handled by a daily check, where the DC is equal to the number of soldiers you have. If you are fully staffed, your land will only ever be attacked on a 20. If you are understaffed, that number drops by 1 for every soldier, making your land 5% more likely to be assaulted. Over-staffing REDUCES the attack DC. When a domain is attacked, roll 1d20 on the following table, with a penalty equal to the number of soldiers you do have, including excess soldiers, to determine the type of attack:
<1
Major crime incident or civil unrest
1
Wild Animals
2
Wild Monster
3
Bandits
4
Undead
5
Goblinoids
6
Gnolls or Lizardfolk
7
Orcs
8
Barbarians or Cultists
9
Ogres, Trolls, or or Oni
10
Military Invaders
11
Elemental
12
Drow
13
Hag
14
Giant
15
Hydra, Wyvern, or Roc
16
Purple Worm, Beholder, Aboleth, or Mindflayer
17
Fiend
18
Dragon
19
Lich
20
Tarrasque
The result is that, although over-staffing your military does eliminate any chance of external forces damaging your domain, it stifles the population and increases their tax burden in order to do it, making civil attacks more frequent. The crimes occuring might be a corrput police force taking advantage of their superior numbers to abuse the people, or criminals lashing out against the police and state, while civil unrest could be riots, or even outright rebellion- possibly sparked by competing rulers from foreign domains who would like to take your land for themselves.
Taxes
Landowners within another man's domain, be it a duchy, kingdom, or empire, must pay taxes in return for the protection afforded by that ruler. Taxes are usually taken monthly or yearly, but accrue to the cost of the days of protection, multiplied by domain size, divided by the local land-owning population. These rules assume the NPC domain is measured in 6-hexmile hexes and is protected by at least one keep per hex. Between soldiers and keep, that comes to 142gp per day
The population is about 5 people to a mile, or 225 people to a 6 mile hex, so that comes out to about 5 silvers and 6 coppers per day, per person. Now, obviously, only skilled laborers can afford this. As such, in well-defended lands, the vast majority of people are impoverished, living a squalid lifestyle as servant-peasants on the estates of the landed nobility and wealthy professionals, who pool their combined labor to make up the tax debt in goods and services. In lands which tax people fairly, they are often sorely underprotected, and face frequent invasions from all kinds of marauding forces.
For reference, in order for all unskilled labor to have a lifestyle above squalid, tax per person ammounts to 5 coppers per day, making for a total tax income of 11gp per day. The keep either never got built, or is an abandoned ruin, because they can't afford to run it at all. All tax money goes to the 5 soldiers on patrol. There is a 30% chance of an attack happening somewhere in the domain every single day. When an attack happens, there is a 25% chance of that attack coming from a criminal or civil unrest, while the remaining 75% of outside marauding forces include everything from wild animals, to bandits, to zombies, to goblins, to military invaders, and even wyverns. In short, the homelessness and mass servitude of the people really is for the greater good- because it is better to be homeless and alive, than wealthy and dead. The civilization described here would be a wild, dangerous, and chaotic place to live, despite the well-meaning leadership.
We can create the alignment personality of a nation through this taxation mechanic. Simply by controlling the number of soldiers hired per hex by a government based on its alignment can be used to calculate the tax burden of the people who live there, and the domain attack DC, as well as the range of what kinds of attacks may occur.
L
N
C
G
20
15
5
N
25
20
15
E
30
25
20
Notice that the CG aligned nations fit our wild and dangerous civilization example above.
