Lusaka Zambia 40km Low-poly (Polygon mesh 3D model) is available on CGTrader for $49. Original author: CityArt.
C4D (Cinema 4D, filesize: 130 MB), OBJ (OBJ, filesize: 138 MB), FBX (Autodesk FBX, filesize: 128 MB), 3DS (3D Studio, filesize: 35.1 MB), 3DM (Rhinoceros 3D, filesize: 103 MB), STL (Stereolithography, filesize: 101 MB), DXF (DXF, filesize: 114 MB)