How to Make Money in Bannerlord: Fighting and Raiding
One of the most basic, easiest and quickest ways to earn denars in the early game is by hunting down raiders, looters, and other bandit groups. Most of these groups range in size between 6 - 19 troops, but you can fight them with much fewer if you have a handful of experienced troops yourself. If you feel confident on horseback, you can even fight groups of bandits on your own, picking them off one by one with successive charges. However, while this may provide more of a fun challenge, it will be much slower than it needs to be.
You will find groups of bandits throughout Calradia. There is certainly no shortage, but they are most concentrated near trade routes between major settlements, or nearby their local hideouts. The hideouts themselves can also be assaulted, providing you with a base amount of denars in addition to that which you gain from the loot. Whatever you choose, all you need to do at the end of a battle is stash as much loot as you possibly can within your inventory, take as many prisoners as you can, and then proceed to the nearest large settlement to sell it all. The prisoners you can sell at taverns, while any other items can be sold to regular merchants.
In addition to hunting down groups of bandits, you can also plunder villages for their wealth and sell even more prisoners after the battle. This should be done with caution however; if you plunder the village of an otherwise neutral faction, that faction will declare war on you. It is therefore recommended that you only plunder villages of enemy factions, preferably while you are a member of another faction so that you will have their support. Furthermore, you should consider the impact of your actions in relation to how your companions will respond. If you have companions with merciful traits, they will not respond well to your plundering, while those with cruel traits will encourage it.