So, uh, so my game went pretty far off the rails and now I need to figure out what the housing market is like in Sigil, because the party wants to buy a house. So they can reform some thugs that tried to mug them in the lower ward, teach them to read, and help them get honest jobs.
This will probably end poorly for them, but the thugs are all at negative HP (kept conscious with smelling salts) and are hardly in a position to do anything other than agree and get carted around for the moment.
So. Uh. Yeah. Houses.
D20srd has a chart with the guidelines that a simple house was 1,000 GP, a grand house was 5,000 GP, and a mansion is 100,000 GP ... but 1,000 GP to own a house seems pretty low. I mean, I guess it might be a reasonable price to own a one room shack in the Hive, but does anyone actually buy houses in the Hive, or do they just shank the previous occupant?
Upshot of the below: I think 1000gp is a perfectly good cost for a house in Sigil, and one outside the Hive at that. The Hive probably has very few freestanding houses anyway, given the unlivability of parts of it like the Slags and the density of poor housing that the rest of the population will be wanting. If the party has the money, then for a 1000gp house in the Lower Ward, I would suggest making them deal with a shark of a real estate agent; Sigil can't expand outwards, so new construction will be rare and the cutters who trade ownership probably hold on to their titles carefully. If the PCs give the remotest hint of needing the house fast, the price could easily double.
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Bear in mind that a skilled hireling makes 3sp per day, which we can figure is the wage of something like a carpenter or plumber doing standard trade work, and many people are untrained and will make 1sp per day. Let's suppose that a husband and wife both work, the husband at trained wages and the wife at untrained, bringing in 4sp per day, and they have 2 kids, for a total of 4 mouths to feed (and many Sigilians will have more). They work 6 days a week, taking in 24sp per week.
A pound of bread at SRD prices is 4cp. Standard wheat bread in our world comes in at about 75cal per oz, or 1200cal per pound. Figure an equivalent cash-per-calorie cost for similar starches like potatoes or turnips. A half-pound chunk of meat is a rich 3sp for 500 calories (typical ground beef), and a half-pound of cheese is about 900 calories for 1sp. Those are far too rich to be standards at this level of living. Let's figure the family's basic diet is fairly monotonous, mostly bread or similar starch, and getting along on 1800 calories a day on average: a pound and a half of bread/beans/whatnot, with 2oz of meat and 2oz of cheese one day in seven. Dad drinks a 4cp mug of ale every day, and Mom and the kids get one on Sunday too. Total food and drink cost for the week: 4sp ale, 3sp meat, 1sp cheese, and 16.8 for "bread": 24.8sp. Oops. Well, let's make meat once every three weeks and have the family getting along on 1500 cal/day on average: now they're eating 20sp and saving 4. (Think they could save on the ale? Hah.)
So they save 4sp a week. Make it 8; they can probably get better prices than adventurers. Over a year, that's 400sp, or 40gp.
Of course, most Sigilians will be dressed. A peasant outfit is 1sp, and may get changed out about every six months if the wife's good with a needle. So clothing cost isn't bad, about 1gp a year. 39gp left. Dad's trade needs his tools, a 5gp artisan's toolkit (dream on for masterwork), leaving 34gp. Household commons that on average might need to get replaced once a year through breakage, theft, or repair needs from the SRD list include 365 days' supply of firewood, call it 3.5gp, leaving 30.5gp; a waterskin, 1gp, leaving 29.5gp; soap (they don't bathe that often, but a pound a year for four Sigilians might do), 0.5gp, leaving 29gp; Mom's sewing needle, 5sp, leaving 28.5gp; and let's let a blanket and a bucket, 1gp, stand in for basic furniture that wears out or needs fixing once a year, leaving 27.5gp. It's probably not unreasonable to call for another 7.5gp in further costs (bribes, thefts, unexpected illnesses, etc.) over the year, leaving them 20gp. Finally, taxation and/or tithes may take another 5% of yearly gross income, or 6gp, leaving 14gp. (8gp if they tithe 10%.)
If the owner of a 1000gp house wants to make his money back on it in 30 years, that's 33.3gp rent per year, or say 3gp per month. These people can't pay that. Living on the edge they can manage about 1gp per month. Suppose they're careful with their goods, they live close to the bone, and maybe they manage to eke out 3gp per month (they're probably sweating it); then this is going to be a rental.
So no, a 1000gp house isn't going to be standard in the Hive. 1000gp in the Hive probably owns you a small apartment tenement, with a half dozen families paying rent of less than 1gp. Someone who can scrape together 1000gp is making more than your average hireling wages, or has maybe one kid and has been pinching pennies for years. A wizard or adept who can cast 1st-level spells can already command enough to save up for such a house quickly -- even if he only has 1 customer a week, he makes 4x what the hireling and his wife do. Even an entry-level adept or talentless wizard with some 0-level spells who has 1 customer a week in the Hive for a read magic or cure minor wounds spell makes twice what the hireling does. These guys can rent. Or if they're assiduous, they can save up. It's treasure-hunting PCs that don't get killed that can buy houses.
I wrote up a few options here, though I now think "bachelor pad" housing ought to be cheaper than the 3gp per month I list there; maybe 2gp per month. I don't even bother with the higher cost places; the people who can afford those are PCs and people PCs deal with, and there are more of those in Sigil than in other cities but they sure aren't the teeming masses.