How do you answer 'What is the best service you ever received as a customer'?

Just be honest and tell the employer about a time when you were happy with the service that someone gave you. Were they especially kind or attentive to you? Did they help you find something that you otherwise were not able to find? For me, an example may be the time when a sales person called several stores in order to find me the exact item I needed. I was able to get that item on time because of their help. I hope that helps you out.