I'll come right out with it: I didn't have much of an interest in touring a red light district.
Luckily someone strong-armed me into it, and here I was, walking (not working) the streets of St. Pauli. My guide was tri-lingual (German, English, Spanish) Sebastián Saavedra, a professional guide who passionately shares his neighborhood with curious visitors from all over the world.
Of course Sebastián knows the sex business of St. Pauli, after all it is one of the most famous red-light districts of the world, but he also talked much about the neighborhood, regular people living there and knew the general history of the place. I had almost forgotten about the Star Club (https://en.wikipedia.org/wiki/Star-Club), that used to be in the midst of it all, where The Beatles played before they'd made it big.
Regular tours were Euro 20/person–at time of publishing
>>>A big thank you to Curio, A Collection by Hilton (curiocollection.com) for flights and one of its remarkable hotels, Reichshof Hamburg http://www.reichshof-hotel-hamburg.de/en/), for accommodations.