A tough customer that I went over, I had one just the other day at work, this man was kind of belligerently just loud and angry, and by the end he was smiling and laughing with me when he walked out. I did that by showing empathy, letting him know that I understood what he was feeling and why he was feeling that way, sharing a personal experience I had where I was equally as frustrated about something, and then cracking a couple jokes at him, and just keeping a smile on my face the entire time, and he actually stood in the office for another five minutes just kind of joking with me, and when he left he was giggling, so that was a win for me.