Use one company for testing and reports, another for consulting, and even a third for the actual work. That's right: There might be three companies involved for a green remodeling job that leans in your favor. 

Everyone knows it is important to get more than one estimate. Not as obvious, though, is that using the same or overlapping companies for your remodeling project might be a conflict of interest that is not in your favor. 

Keeping this separation of companies is very important for your bottom line. It is as important as multiple estimates,  if not more important to to your successful energy-project. 

Take it a step further. Make certain there is no connection between the different companies or, if there is a connection, make certain you understand what it is. Businesses with two different names, but basically the same or overlapping company ownership, are not uncommon in this field.