He just sounds like a twat, to be honest. My front door opens onto the street, and I have neighbours opposite. For new clients, I normally wear a fairly normal dress, so it's OK to open my door normally, but if it's a regular I may only be wearing a babydoll or something, so obviously I stay behind the door!
TBH, I think it's a good idea to dress fairly normally for the first booking with a client, in case anything goes badly wrong and you need to move.