The DeLorean's body is comprised of stainless steel body panels over a fiberglass body. The stainless steel panels are very thin and not as heavy or thick as most people think they are.
No special care is needed in keeping the body looking beautiful. It is maintained about the same way you clean your stainless kitchen sink. Minor scratches and scuff marks are readily removed with a "Scotchbrite" pad by rubbing with the original grain of the panels. The only precaution is to minimize any rubbing across the grain of the panels as this may scuff them. The best advice to keep the stainless steel in good condition is to keep your DeLorean clean and avoid using metal abrasives when rubbing out scuff marks. The owners manual advises "Wash panels with warm water and low suds detergent. Stains of tar or grease may be removed with gasoline or white mineral spirits." How many auto manufacturers recommend using paint thinner to remove stubborn stains from the body? Larger/deeper scratches and severe abuse require the use of the original texturing jigs to get the grain correct. These are not difficult to come by and there are numerous service centers (especially the larger original dealerships) that have this expertise.
The panels come easily off the car and are therefore easy to work with in the event of a dent. Minor dents can be readily removed by those skilled in working with stainless steel, but catastrophic crashes require panel replacement. Those skilled in working with stainless steel tell me that dents can often be removed with nothing but the proper application of heat.
The stainless steel panels are not indestructible and some seemingly harmless acts may result in severe damage to the finish. Contrary to popular belief, SOS pads or steel wool damages the stainless steel. Steel wool leaves small metal particles (from the steel wool) embedded in the grain of the stainless steel which rusts -- giving the impression that the stainless steel is rusting. Also metal abrasives (SOS pads) act as reducing agents, chemically reacting with the outer oxidation layer of the stainless panels and destroying some of their stainless properties. Iron compounds in general react with the steel -- bleeding on your car or leaving a slice of bologne on your hood may cause persistent blemishes that are difficult or impossible to remove. Although very resistant to nitric acid, SS304 is not very resistant to phosphoric and some other acids.