Tannhauser is a working class neighboorhood. No nobles will be found perusing it’s small market square, or the few shops there. The wealthy and powerful have holdings and investments in Tannhauser, but few would be willing to be seen on those dank streets.
In one word, it the smell. The neighborhood’s wealth is built on butcher shops, and tanneries. Bovines by the hundreds are slaughtered every week. The meat is hung in thick walled rooms to drain while the hide is carried across the main boulevard to the tanneries. While the meat is being sectioned and cut, packaged and sold, the hide is scraped and dried and treated.
The finished leather is then sold to the leatherworkers, cobblers, tailors, saddlemakers, and the whole plethora of trades who do brisk business in leather. The Butchers Guild, the Tanners Guild, and the Leatherworkers Guild all have heavy sway in the area, likely more than any city official, or would be ruling noble.
The youth gather in street gangs, most for protection from the gangs of other youths, the Fish-Wharf boys or the SootHammer gang, or the clusters of rapier wielding dandies who come slumming in the dirty taverns and brothels. Of course, there will also be the resident thieves guild and the guildmaster.
The street urchins and most of the neighborhood gangs pay him lip service, and the nobles and officials know that as long as they work with the boss, and the boss makes the appearance of being an upstanding citizen life will be much more bearable.
To get a better feel of Tannhauser Street watch The Gangs of New York I know it’s a Leonardo DiCrapio movie, but it pretty darn good. Just my two cents