Finding out a lord's cash on hand.

I’ve been statting up the domains run by a PC’s villainous brothers and ran into some questions.

Their titles are both King, but they’re from a backwater area and correspond to dukes from the main rules. I mapped both their realms and divided them into domains of three to eleven six mile hexes. In each realm there’s the king, then the jarls, and the greves below them.

I worked out the families, income, taxes and garrisons at the greve level then paid those taxes up to the jarls who payed up (including 20% of the taxes they receive) again to the Kings. This data, when combined with the income from their personal domains, gives a monthly income for all the nobility. Then I subtracted the monthly upkeep of a member of their social class to get their net profit.

Is there any way I can turn that monthly profit number into a likely war chest for hiring emergency mercenaries, paying bribes and ransoms, building ships, etc?

Also, I generally picked a monthly upkeep that was around half of their after-tax/tithe/garrison profit. This gave me income that was a sight higher than the estimate on the revenue by realm table. Are my Thanish nobles living too frugally?

Double also, since this war will be fought by not-vikings against two peninsular realms, ships will play a big part. Are the rowers/marines mentioned in a longship simply hired as mercenaries of their troop type or should I add the wages of rowers and sailors to those of light infantry to get sea-raider pay rates? I worked out the cost to hire a longship by looking at the price of buying a war elephant as a slave-soldier, and can use their price to find out how many are on hand in a given market; but that will have to be recalculated if I’ve got the marines’ wages wrong.

I don’t think there’s a table for that…yet…