Guys, I suspect if you want a clear gauge how difficult the contract will be, look carefully at the amount of reward offered. There is some indication that the reward indicates how tough a contract is going to be.
Been watching Zosh127’s youtube, and he got a contract which was 3-star but offered a lowly 800+ bucks. True enough, while the numbers of bandits were large, most of the bandits are thugs and not raiders so he won easily.
I suspect certain “events” trump this however. Events like “You’ve found a bandit leader in the camp!” which significantly boosts the difficulty, but will also reward you much much more than the original amount once completed.