If you give real estate developers too much of a free hand, they will plaster over every bit of common space with cramped flats or other abominations. There's even a word for it in Polish - "patodeweloperka". It's most prominent in Cracow (alleged ties of real estate companies with local officials), also in Warsaw and its suburbs. In Gdańsk, it's suspected that many old unused buildings in attractive areas had an "accidental" fire.