Anyone who owns a classic car usually takes loving care of its maintenance, upkeep, and preservation, regardless of whether it is a high-priced classic that yields returns or a former "everyday hero," such as one of the all-too-often carelessly worn "utility cars" from the 1970s and 1980s. They polish and shine, applying tinctures, sprays, and waxes, massaging them into the metal as much as possible. However, those who devote themselves to caring for the exterior should not neglect the interior of their classic. Seat cushions visibly wear down over the years and decades, wood ages, instruments let their needles droop, carpets show the marks of countless shoe soles, plasticizers in materials evaporate, leading to unsightly cracks - in short, there is plenty to do "inside" as well.