How could you give a customer an Extra mile in your opinion ?

Understanding the Customer's need ,rectifying the error if any and assisting him/her  or going out of your way to make sure the issue has been resolved would make him/her a happier client .

if I put my self in customers shoes for that moment switching over my role from a sales man to customer surely I will know how I can get best out of this deal and then I can offer extra mile for that customer