I was thinking more of a budget style thing. After all, mercenary companies were notorious for being up to their eyeballs in debt and obsessed with looting.
This! Make everything very expensive, so its impossible to not be in debt, while still doing actions. However, players can take out loans, but should pay interest in specific order or get some way around the debt. Like creating situations where bank gets destoyed or cannot longer function to demand payment of debt using their mercenary work, or something else. Players should constantly look at their debt score, constantly look for how to pay it or do something else about it, constant "we need to buy money".