Websites like Care.com connect parents with babysitters. The company does all the background checking and other due diligence to put parents' minds at ease. Of course, you can appeal directly to people in your personal network, but if you're looking to generate recurring revenue sign up with a site marketing to parents looking for child care services.
One of the most underrated freelancing sites ever. The site started as a place where you could get paid to do short tasks for just five bucks. Over the years, it has slowly morphed into one of the biggest gig/freelancing sites where you can now charge any amount to do all kinds of stuff for other peoples. Anything from serious stuff like copywriting, translation, voice over social media management to silly stuff like prank calls and everything in between.