The Sleuth Sisters have different life scenarios. Retta had a husband she loved very much, and she was forced into single living by his death. Barb chose to be single and is therefore the most idiosyncratic of the three. Faye has Dale and always has had. After decades together, they form a cohesive unit and respond to each other's personalities almost without effort.
How do their lifestyles affect the stories? Well, Barb is certainly sure of herself, which makes her a natural leader for their firm. She's also got a chip on her shoulder about women being relegated to second place. Retta isn't shy about using femininity to get what she wants. Often lonely and bored in her empty house in the country, she tends to take chances neither Barb nor Faye ever would. And Faye doesn't mind being the backup, the organizer, the researcher. That might be partly because of her happy home life. She's got nothing to prove to herself or to anyone. She just wants to help people