How much oversight do I have to deal with? Because it’s not much of a dilemma if I can take the money and also depict the person as I see fit. Assuming that the subject has full editorial control, then, I suppose it depends on whether I think I can write a narrative that pleases both them and me simultaneously. After all, what I take to be their worst traits might be exactly what they take to be their best.
But my guess is that the underlying question is supposed to be something like “would you sacrifice your integrity for money in this situation?” If that is the case, then my answer is “no.” I have way too many writing projects that I actually want to get done to work on any that I can’t be happy with. And given the cost of academic books, I might be able to make a good pile of money from one them, too.
Just kidding! Almost all of that money goes to the publisher.