When only the door step corner of the door (which is the lowest and therefore will be most quickly affected by rust) can no longer be restored, you may consider replacing the entire section of the if available for your Volkswagen Bus.
You can also consider replacing only the step or a part of it, in order to preserve as much as possible the original sheet metal, and with a little bit of know-how, none of this will be visible afterwards. This is also cheaper than replacing a complete section.
The true restorer will always choose to keep as much of the original sheet metal as possible and restore with as little replacement as possible. Most professional restorers must consider the hourly rate, they will in most cases choose the method that takes the least amount of time and then a full sheet metal replacement will often be more cost effective.
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