20ft Shipping Container CSAV v2 (Polygon mesh 3D model) is available on CGTrader for $29. Original author: dragosburian. Specs: 55982 polys, 57654 verts.
BLEND (Blender, filesize: 17.3 MB), OBJ (OBJ, filesize: 7.67 MB), FBX (Autodesk FBX, filesize: 9.28 MB), STL (Stereolithography, filesize: 4.34 MB), DAE (Collada, filesize: 8.37 MB)