Harvard psychologist Amy Cuddy says people judge you on 2 criteria

Trust and respect are key when a solar salesperson engages with you.  Take your time during your solar power decision process.  A solar salesperson that trusts and respects you is not going to pressure you into signing contracts on the first day you meet them.    A third key component is Expertise.  What do they know?  How long have they been doing it?  How many completed projects do they have?

A key way to quickly test if you can Trust and Respect a solar salesperson is to take your time making a decision on who to start the project with.  A solar salesperson that can be trusted and respected will be absolutely fine with your due diligence measures.

http://www.businessinsider.com/harvard-psychologist-amy-cuddy-how-people-judge-you-2016-1