Beginning characters must pay for every short-term need, including room and board. Such things will be more expensive on a pay-as-you-go basis. Once they've earned their first 100 experience points, however, they can consider ongoing expenses to be covered by a monthly upkeep expenditure. Add 50 points to the character's current accumulated experience and drop the last two digits to get the monthly upkeep costs.
This may seem like a house rule, but it isn't; it's a restatement of a rule given in Vol. III, The Underworld & Wilderness Adventures, page 23:
"Player/Characters must pay Gold Pieces equal to 1 % of their experience points for support and upkeep, until such time as they build a stronghold. If the strong- hold is in a wilderness area all support and upkeep costs then cease, but if it is in a village or town not controlled by the player/character then support and up- keep payments must continue."How much characters spend per month can be used as a rough guide to what kind of conditions they live in. The 1 GP/month PC has a corner to sleep in somewhere and at least one meal a day, probably stew. The 10 GP/month probably has a small room in someone's house, or at an inn, 100 GP/month is a suite of rooms or a one-room cottage. PCs must pay for consumable items and anything else take on expeditions (rations, torches, arrows,) but maintenance costs for durable items like armor and simple housewares (a couple candles per room, a couple pots in the kitchen) can be assumed to be included as a part of upkeep as long as the monthly cost is more than twice the full price of the item.
Since barons have a monthly income of 10 gp/inhabitant and clerical founders of churches or abbeys have a monthly income of 20 gp/inhabitant, I'd rule that taxes or tithes in a territory are 20 gp per person, but half the money raised in a barony goes to maintenance of the keep and barony; clerical lands produce twice as much because of additional contributions or donations from the faithful. Wizards in the LBBs do not get an income, but there's some leeway in how to interpret this. Perhaps wizards can't build strongholds or raise taxes, or perhaps they can, but don't attract inhabitants, and one of the following is true:
- they must pay standard upkeep as if living in a city;
- they can make investments to attract a population, but all the income collected goes to support the territory;
- they don't pay upkeep, but maintenance and supplies are assumed to be acquired through supernatural means;
- they collect 20 gp/inhabitant, but half goes to upkeep and half goes to a lord or patriarch; they must make investments to get any actual income.