Authority for Salespeople

There are many ways to acquire authority in a sales profession. One way is through the time spent on the job and experience, but another key factor that helps people reach their goals of acquiring this type of power is creating trust with customers.
But how does one create trust with customers? Some say it’s by being upfront about your intentions from day one; others believe you can do so without revealing too much information at all times because there will always be something new for them to learn about when they talk to you again next time around.