I had been planning to part out a donor car this way for quite a while, so I'd built up a pretty decent collection of cardboard boxes for just that purpose. Buying new boxes quickly turns into a major expense, so it's best to recycle used ones.
When compared with the revenue produced by selling a used car as a whole, intact unit, many sellers find that selling a car in the form of individual pieces is considerably more profitable. This difference is especially true if the car is in poor condition or not running, as many of the individual components may still function even through the car does not run on its own. When parting out a car, it is not uncommon to find that pieces of a car, especially of a non-running car, may sell for as much as the entire vehicle itself, justifying the investment of time, knowledge and sweat required to part out the vehicle.