My observation is that many sales reps today try to relationship-sell instead of presenting a solution to the customer's problems after asking a thorough discover / fact finding. It's in the preparation (before the meeting), the approach, and then during the discovery where trust starts to be built. A former business leader, manager, and mentor of mine, Tom Turvey, told me "Don't focus on if they like you, if they trust you, they will respect you, and usually people you respect you eventually like."
Merriam Webster' Dictionary defines trust as "1 a : a reliance on the character, ability, strength, or truth of someone or something b : one in which confidence is placed. 2 a : dependence on something future or : HOPE"
To become a trusted advisor you must first be honest, blunt but courteous, be a person of your word, and offer sound advice as if you were presenting to your own mother. Being a trusted advisor takes focus, effort, and commitment, but it offers you a name for yourself that is much greater than "Sales Rep" or "Account Executive," it's "Trusted Advisor." Who would you rather do business with a Sales Rep, an Account Executive OR a Trusted Advisor?