Opel Vectra B Sedan Facelift (Polygon mesh 3D model) is available on CGTrader for $65. Original author: Carmodels3D. Specs: 315000 polys, 300000 verts.
MAX (Autodesk 3ds Max, filesize: 33.6 MB), OBJ (OBJ, filesize: 38.1 MB), FBX (Autodesk FBX, filesize: 14.5 MB), MAX (Autodesk 3ds Max, filesize: 33.6 MB), 3DS (3D Studio, filesize: 13.8 MB)