If your car suffers a very light scratch, you might use a bit of touch-up paint to cover this over, and the car will look like new again. However, any type of auto body repair that requires more than touch-up paint should be left to a professional. Rather than buy a dent repair kit or try to sand down a dent and paint over it, consider some reasons why you should always leave this work to a professional.
The materials used for auto body repair are very hazardous to your health; fumes from paint, filler, and paint stripper or solvents are extremely damaging to the eyes and nasal passages. Repairing a car's body can also mean creating a tremendous amount of dust that can settle in the eyes and on the skin, causing irritation. A plain dust mask and protective eyewear are usually not enough to protect you from these hazards; a professional repair person will usually wear full protective gear, including protective clothing, and their shop will have high-quality, commercial fans and vents for removing all those irritants.
It takes longer than you may realize
If you make an appointment with a local smash shop, and they tell you that they will need to keep your car for a few days, this isn't necessarily because they're overbooked. Auto body repairs usually take longer than many people realize; a car may need to be put under hot lights for several hours to help paint dry, and materials like filler and adhesives also may take several hours to dry, even when exposed to heat or dry air. A car owner may get frustrated with how long it takes to handle all these tasks properly, and then rush through their repair work, only to wind up with dripping paint or adhesives that break down and soon fail to work.
Kits don't always do the job
A repair kit you buy at the auto supply store may help to bump out some minor dents and dings, but any type of deep scratch or other such damage will need more specialized tools and knowhow. If you don't pull out the dent properly or fill it with the right materials, this can weaken the body of the car and allow for greater damage the next time you're in a collision. You may also need different tools for repairing parts like bumpers and window frames. A professional shop will have all the tools and equipment needed, and the knowhow to perform repairs properly.