The process of working out details of a "Mixed Economy" is more involved than I anticipated, but I think it is worthwhile. I think it is important not just to get away from the whole modernistic consumerism dynamic, you know, where the group can go into any city and easily buy anything imaginable or desired with a neatly packed pouch of coins. I also think that creating such different styles of economy actually contributes to a very real distinction when say, the group actually visits some enormous imperial city somewhere that *does* have an advanced coin-based economy, banks, and that kind of thing. Over time, I have been establishing a sort of dynamic where barter economies or "Mixed Economies" are actually the *norm*--while super-advanced coin-based economies are at least somewhat unusual.
It's an entirely different economic paradigm than what we are presented with in the Player's Handbook, of course.
When I ran a viking game using modified Runequest, I used abstract Wealth rules below.
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Rather than keeping track of detailed property transactions, characters have a general Wealth level rated from 0 to 10. Equipment is rated in terms of what Wealth level it is standard at. If your Wealth level is equal to or greater than the item, it is assumed that you will have it. Characters will also have a ranking within their Wealth level, from 0 to 9. So a character with Wealth 5.9 would be "Comfortable" below, but almost on the edge of "Well-to-do". The ranking does not make a practical difference in buying, but keeps track of pecking order within your wealth. Exceptional expenses or gains may change your ranking and eventually your wealth level. The wealth of relatives is somewhat tricky to separate. In general, the descriptions below apply to the principal members of a household: patriarch or matriarch and their spouse, along with eldest son. Younger members of the family will have correspondingly less wealth, usually 1 or at most 2 levels lower.
0 : Thrall
Thralls are technically property of someone else. They technically may own property and even do business, but they get paid nothing for their work and thus will own very little if anything. A typical thrall is worth about 5 milk-cows.
1 : Destitute
Someone who is free but owns virtually nothing but clothes and a few personal effects. This may be a lowly servant, wanderer, or newly freed thrall.
2 : Poor
Typically a free servant, who will have a marketable craft and some savings. This might also be a farmer on hard times who is living with relatives.
Equipment: simple items such as a knife, bow, and craft tools along with perhaps a few livestock (~1 milk-cows worth).
3 : Struggling
A typical skilled huscarl, who owns no land but is well paid for his hazardous duty and collects loot in addition -- or alternatively a poor farmer with only a small cabin and a few livestock, and perhaps a thrall or servant.
Equipment: an axe, shield, and a leather jacket or jerkin. A huscarl may own a horse.
4 : Common
A common farmer, with a modest longhouse, a few (2 to 4) thralls, and around 6 milk-cows worth of various livestock. Alternatively, a non-landowner with means, such as a master craftsman or reknowned huscarl.
Equipment: a sword, shield, metal cap, and leather armor for fighting. A pair of horses and a simple fishing boat (4 meters long) for travel.
5 : Comfortable
This is an above-average farmer, with 4 to 8 thralls or servants, and around a dozen milk-cows worth of livestock.
Equipment: a sword, shield, helmet, and metal-reinforced leather armor. Possibly a small knorr (merchant ship), along with a fishing boat.
6 : Well-to-do
This is a well-to-do farmer, with around a dozen thralls/servants for the homestead and a significant herd of livestock. They will need to drive the herd to more distant pastures in the summer. They may have a few (1-3) huscarls, but may not.
Equipment: a sword, shield, helmet, and a chainmail vest. A medium-sized knorr (merchant ship) for the household, plus several fishing boats.
7 : Wealthy
A truly wealthy farmer, with an extended estate and 1 or 2 score of thralls/servants, along with around 6 huscarls, and an extensive herd of livestock (100 or more cattle).
Equipment: a fine sword, helm, and chainmail hauberk. A military longship for raiding along with a large merchant ship.
8 : Very Wealthy
The equivalent of a lesser jarl in classical viking culture, who rules over over a county-sized region. He would have perhaps a dozen huscarls but could easily raise a force of over 100 men.
9 : Rig-Jarl
This is a powerful earl or rig-jarl, who rules over a town or several counties.
10 : King
This is a notable king, a level not currently seen in Vinland.
Link:
http://darkshire.net/jhkim/rpg/vinland/rules/wealth.html