My husband used to take care of the business part of this, and after he died I found I wasn't really any good at it. I hate remembering who owes me what and bugging them if they haven't paid me.
I've been a teacher at the college level, in composition mostly, and I've been an editor on magazines.
You've either got to find a way to make your continuing characters insteresting without making them maudlin or overwrought, or you've got to put more emphasis on the suspects.
Everybody is a True Believer. Everybody has a little nugget they're convinced of that is the opposite of the nugget on the other side. And they're convinced it's fact.
