To take a step back, it is important to clarify that neither utility company APS or SRP offer a free energy assessment and companies may be curtailing off the utilities’ energy efficiency program. You can call APS and SRP directly or visit their website for an approved contractor list.
APS and SRP rebates are only available to file through approved contractors, and homeowners must sign an APS and SRP audit form during the initial energy audit (the true way to tell if you are having a certified APS and SRP energy audit done).
If a single company is offering both a free energy audit and a paid energy audit, a red flag should go up in your mind telling you this is a company you do not want in your home. Here is a chart comparison of free energy audits and a utility-sponsored paid audit: