It also depends some on what they are looking for in a mercenary, many are probably not much better than ruffians and bandits while others might be more of a mercenary army where you'll have to hire quite a few of them at once... neither might fit some.A family in need of protection might have some general guards that hangs around, but also specifically appointed guards for the family members. They might want a guard that they can feel comfortable with and maybe even have a friendly connection too, or they might look for undercover guards, like a guard posing as a hand maiden or a servant.Many will of course want a female guard for their daughters or wife's because they assume that nothing sexual will happen then, but that is naive thinking if you read Janine's story.
Individuals might see themselves as able to acquire wealth or power in the aftermath, whether it be rewards for service or just looting afterwards, but I liked them being united so we would have to unite to battle them.
Finally I finished my first part. A slow entry into the story. Feedback here or per pm please.
As far as the cult I was seeing them as out to kill an entire city. It could be a sacrifice to Zeirst, or it could be to bring Zeirst's master to manifestation, but I liked the idea of them ironically having a unity of purpose that the fractious city does not, even though that purpose is wholeheartedly evil.