A few years ago, Kevin Paffrath, a 29-year-old real-estate broker and father of two who lives in Ventura, California, earned most of his income from commissions on home sales, and kept up a side gig recording online videos about home buying.

Today, he’s MeetKevin, a YouTube influencer with 1.7 million subscribers. Most days, he live-streams on the platform for several hours, talking about the stock market and doling out investing advice in a rapid-fire, self-deprecating manner. He banters with commenters, hams it up with silly British accents and sips coffee in front of a wall in his home studio hung with brightly coloured cartoon posters and a turquoise electric guitar. In addition to the live streams, he’s made hundreds of videos on a range of investment-advice topics.