You CAN become a mercenary for a faction. Ask a noble "do you have a task for me" and he might ask you if you are for hire as a mercenary. I do not know if you need rep with that faction or if you need renown. yah you pretty much are a mercenary as long as you don't pledge your service to them or become a vassal.
The point is, you can vote in Mount and Blade Bannerlord. The system is kind of confusing, and the player won’t always have access to it, but it can prove helpful. The idea is called Fief Voting, and it has a lot of mechanics at play. The most important use of the Fief Voting system is to enact Kingdom-wide laws within your realm.
Hunting mystmountains are just a way to get renown, but after you army size has reached 50 it will become worthless, at this point just rely on mercenary payment start following the marshal or quest for Knighthood orders. This mercenary stage will last a long time, be sure to keep switching factions for troop variety.
If affiliated: first you must become a vassal. There are two ways to start your own kingdom: Capture a town or castle and request it be given to you. If your liege rejects you may rebel. If you are a woman and married, talk to your husband. He will support you as a monarch as long as you've got any town or castle as a fief. xoTWE.
