Hearts of Stone
Any significant amount of loot is really heavy in silver, heavy in gold, and has negligible weight in gems or jewellery. Copper pieces, you say? Faugh, heroes have no truck with such piffling trifles.
The $ sign represents a silver piece, which historically weighed 6-8 grammes. Rounding that off to allow for the weight of coin pouches, boxes etc. it's assumed that a pound of silver is worth about $50.
Gold is worth roughly 20 times as much as silver, so a gold piece weighs as much as a silver piece but is worth $20, and a pound of gold is about $1,000. Unless you have the Noble or Rich Edges, you're not used to dealing in gold pieces.
Gems and jewellery are worth whatever the GM feels like; there are about 2,270 carats to the pound (we'll round down to 2,000 to allow for packaging and keep the maths easier), and gems are worth $1 to over $10,000 per carat, depending on their type, their quality, their cut, and many other factors. You are likely to get roughly half this when you fence them.
Weapons, armour and other equipment your enemies have no further use for can typically be sold for half the list price. However, leather armour and clothing are generally too badly damaged to be worth anything by the time you've stabbed the wearer to death.
Wages and Upkeep
Your starting wealth ($500 for most characters) represents roughly one month's income or expenditure, about the same as a mercenary Man-at-Arms – the average person thinks of you as a mercenary, because you do violence on behalf of rich people for money. Your food is plain but hearty, and you stay in a double room at inns.
With the Poverty Hindrance, you make about half that. Your food is cheap and often nasty, and you have to skip a meal every few days. If you stay in an inn, you sleep in a room shared with half a dozen other people.
If you have the Noble or Rich Edges, your income is about three times the average. Every meal is a feast, and you stay in private rooms.
History buffs: Yes, these numbers are anachronistic; they represent a tradeoff between historical accuracy, playability, and me not wanting to rewrite the Gear chapter…