The so-called 'Gypsy market' is not for everyone. The city's trash-pickers and junk dealers, plus sellers of vegetables, new clothes and bulk items, lay out their wares in several warehouses and parking lots in this industrial part of town. The brave of heart can find some bargains, collectables and kitsch delights among the junk.
For decades in Gazi, the market was pushed to Eleonas in 2015, and it has changed locations in that area twice already, so you may need to scout a bit. When you get out at the metro stop, walk south until you see parked cars and a church in a traffic circle. Vendors are usually set up in warehouses nearby.