Just a quick and simple guide to show how to reach the black market as a recent update (as of the creation of this guide) has changed the pathing.
How to reach the black market
Firstly make your way to the left of carpet cleaning. The fire escape is the stairway to the blackmarket.
Going all the way to the end, there are a few bags of trash bags near the wall. Simply jump on them, then proceed to jump onto the green electricity box. From the green box jump onto the white electrical box on the streetlight. (hug the streetlight as you jump to make it easiest to land)
From here you can jump onto the fire exit, then simply jump back forth as you make your way up. Then enter trough the window.
Welcome to the blackmarket! The items for sale are purely interior
