I've rarely done out calls so I usually show up in my work clothes. Which is khakis and a nice shirt/shoes. Last time I did in call I wore shorts (no holes; khaki) and a button up shirt. I was barefoot since it was in a beach condo. It was a very sunny day in the spring and I had the sliding door open so it seemed appropriate. Of course, I live at the beach so it's pretty standard attire.
If I were traveling and at a hotel and hosted, I'd most likely wear something similar to my work clothes. Nothing sloppy.