Out of Strife, Prosperity adds the concept of types of wealth holdings.
Estate Holdings - 1 per domain
quote:
Estate Holdings represent concentrated, organized holdings intended to make the most of a domain’s natural resources. These are usually agricultural or husbandry related, although some may involve the harvest of natural resources. Not all domains where such resources are gathered must have these holdings, however. These holdings represent such operations on a scale large enough to influence the fortunes of the master House, generally producing not just enough for those who dwell there, but a surplus that can be sold. In either event, any given domain can have only one estate holding at a time
Lifestyle Holdings - many have additional costs such as defense or power
quote:
Lifestyle Wealth Holdings reflect the sorts of luxuries that only the truly wealthy Houses can afford. They often pro- vide improvements to the living conditions in a Commu- nity or Defensive Holding. Because these Holdings often build into the main keep or seat, some of them also cost points of Defense—such Holdings can reduce the overall defensibility of a castle, and so resources have to be allo- cated appropriately to include them.
Personage Holdings- No limit
quote:
Personage Holdings represent either skilled individuals or small gatherings of such individuals. In general, they require the presence of a Community or Defensive Hold- ing. Unlike with other Holdings, there are no limits on the number of Personage Wealth Holdings that may be purchased in a given domain.
Settlement Holdings - limit based on community or defensive structure size in the domain
quote:
Settlement Holdings require a population of some size in order to be built. Generally speaking, they require either a Community (Hamlet, Town or City) or Defensive Hold- ing (Tower, Hall or Castle) in order to construct. A hamlet or tower may have one such Holding, a small town or hall may have two, a large town or castle may have four and there is no limit to how many larger communities or de- fensive holdings may have. These limits apply to all Settle- ment Wealth Holdings save where noted.
Also adds the concept of resource reduction protection - if a house fortune roll says you lose a the resource you lose less of it. Many of the holdings have improvements such as added the smelting equipment and expertise to a mine.