My favourite amateur sleuth is Miss Marple, who doesn’t have a career, she is a spinster of modest independent means.

My second favourite, Hildegarde Withers, in Stuart Palmer’s books, is a schoolteacher.

Emily andrew in Maddy Hunter’s ‘Passport to Peril’ series is a tour guide.

Carolyn Hart’s Annie Darling keeps a mystery bookstore. Joan Hess’s Claire Malloy is another bookstore owning detective.

Harry Kemelman’s David Small is a Rabbi

J.S. Borthwick’s Sarah Deane is an college professor teaching english.

Auguste Didier in Amy Myers’s Victorian series is a chef. Mrs Jeffries in emily Brightwell’s series is a housekeeper.

Brother Cadfael in Ellis Peters’s medieval series is a monk. Sister Frevisse in Margaret Frazer’s series is a nun.

Katherine Swynbrook in C.L. Grace’s medieval series is a physician and apothecary.

marilyn Todd’s Claudia is a Roman widow struggling to run a wine business

Vicars, housewives, writers, college students, musicians, retirees, antiques dealers…

Essentially, any job which allows the person to do what needs to be done at the time of his/her own choosing, most of the time anyway, gives them time to snoop around and solve mysteries.