Intensive maintenance of the entire interior of the vehicle is involved. The interior of 50-year old cars consists of a range of materials that include the use of different cleaning products and techniques, such as synthetic carpet upholstery (a covering that makes it more comfortable), vinyl, leather, carbon fibre composites, plastics, etc. Vacuum (for suction) is a standard method, and through steam cleaning, liquid, foam chemicals and also through brushes, the stain that is on the cover can be removed. In addition to this, it is possible to polish certain porous surfaces.