We have a regular customer who comes into the dry cleaners where I'm currently working who's always very abrupt and grumpy and very particular about his orders and how things should be and if anything's even remotely off. He's quite forthright in telling us how I've handled it is how I handle all customers is just to be as pleasant and polite as possible. Make sure that I'm using all of my active listening skills and showing I am listening to what he's telling me and then explaining how I can resolve any issues or explaining why we've done something a particular way and just making sure that that communication is there. It's also every single time he comes in it's a good opportunity for me to build up rapport with him and then now that I've built up a lot better rapport with him I find that I can deal with him a lot better than other colleagues who don't have that rapport already in place. And I've built up trust by showing that I'm always just being completely honest with him and I am listening to everything he's saying and now that I've got that rapport and I've built that up it's a lot easier to deal with him. So definitely listening, making sure I'm hearing what he's saying, making sure I'm responding well and making sure that he's understanding my responses and understands what's going to happen next. That's the best way I find with dealing with challenging people.