One of JOHN R. OLSON’s first cars was a Mercedes-Benz 300Sc roadster. He’s been hard to please ever since, and has owned memorable cars from makes as varied as Studebaker and Ferrari, plus a bunch more Mercedes. In each case, he sold for more than he paid—a delightful way to fund a hobby. Like most car enthusiasts, this was not his goal, but he’s not complaining, and he turned his experiences into a book, Make Money Owning Your Car (And Enjoy Every Minute). After discovering he liked words as much as cars, he began publishing the SL Market Letters (SLML), which has been rolling along for 27 years now. Olson has self-published three additional books; the latest, The SL Experience, is one of Amazon.com’s best-selling Mercedes books of this decade.