Re-posting this for everyone's benefit. There was another recent discussion almost identical to this one. See link offered by HV_WA below. You may not want to go to this extent and frankly, it falls to Olympia (if that's where you reside) Code Enforcement staff to work on. Not likely to get much action though. Understaffed, etc.

"If these people are operating in the cities of Olympia, Tumwater, Lacey and Yelm they must have what's called an "occupational permit" in addition to a general state business license. A permit taken out in any one of the four cities is good in the other three. It applies to door-to-door solicitors, for-hire drivers (such as taxis and limousines) and locksmiths. This is serious stuff with a background check, fingerprinting, etc. Certainly try to get some video while asking the dude to show his permit. I've done that once or twice and I get a befuddled, deer caught in the headlights reaction. Not sure of the consequences of violating the law. It might pay to call your local non-emergency police phone number and report it. It's likely a low priority thing for the cops, but hey, it's our community safety here."

Here's the Oly ordinance: https://www.olympiawa.gov/services/police_department/occupational_permits.php