Must the car be washed before returning it ?

My car is incredibly dirty. It's fine to just do a quick check when returning it.

Not washed, smoothly returned the car

Don't wash, I once spent 18 dollars to wash the car in the United States before returning it, and cleaned the interior with a vacuum cleaner by myself. When I returned the car, the other party didn't even look at it. Later, when watching the American TV series Breaking Bad again, Old White's wife became suspicious because she saw a woman washing a rented car at his home. She also said, "Who would wash a rented car?" It was not until then that we Chinese people realized that we were thinking too much. From then on, we don't wash the car when renting it, but we must make sure the interior is clean!