Stop in for a cup of coffee
Suppose the choice depends how bad the body and paint are.
The areas that need welding or reshaping got to go to bare metal anyway.
What's the rest like ?
My car was pretty clean (lots of small dents and dings but basically straight).
The repairs and spot fills were done first. Then the sand down in preperation for the primers.
They just sanded it down and didn't wory much about getting it to bare metal or not.
As I mentioned earlier, the original paint under the window gaskets wasn't touched. That was used for reference during the repaint.