e-Home Automation

I needed someone to help troubleshoot my Nest installation; it had suddenly stopped working (and the previous installers didn’t seem competent to fix it). I found Alex on the Next certified installer site (and see that he’s still listed). Unfortunately, although I think Alex can probably handle the most basic Nest installation, I wouldn’t recommend him. The previous installers had not used standard wiring colors and this seemed to throw Alex off quite a bit; he commented on it several times. Then, although he did use a voltage meter to test the wiring, he also started just randomly touching different wires together. When he got to the common wire, I witnessed the system make a loud electrical popping sound. There was no voltage detected on the common wire after that. He eventually gave up and said I should have the original installers fix it.
I worry a bit that he shorted out the delicate electrical components on the furnace, resulting in a $ 600+ repair cost to me. And I don’t think he should be a certified Nest installer.
Despite shorting out my system and not fixing the original problem, he charged me $ 32.