Years ago, I remember asking an electrician working on a client’s home how a layman like me could tell if the electrician was any good.
He shrugged: “Well, the really bad ones . . . are dead.”
“OK,” I pressed him, “But, how does a non-expert find at least a (very) good electrician? For that matter, how do you ” as an experienced electrician ” tell if a colleague knows their stuff?”
“I watch ’em work,” he said.
Specifically, he explained, he watches how the electrician analyzes the home’s electrical system and wiring, how efficiently they move about, and generally, how they tackle the project at hand.
Makes sense to me . . .
P.S.: Why not simply go by reputation when choosing a contractor?
That’s always a good start, but it simply begs the (circular) question, “what is the reputation based on? (i.e., how do individual customers know that their contractor did a good job?”).
With house painters, the work product is evident; with electricians . . . not so much.
See also, “Identifying Mediocre Electricians ” & Realtors.”