People are always looking to have their cars washed and detailed. You could be a mobile car washer and detailer without having a permanent location. Reach out to people you know or make some flyers and put it in your neighbors' mailboxes. If you want to get serious about it, prop up a one-page website or give out business cards. You can make money quickly doing this.
As an Instacart personal grocery shopper, you will actually be doing the grocery shopping yourself (so don’t crush anyone’s avocados!). Your compensation depends on several factors, like the average size of your orders and average number of miles driven per trip. You can also get tips in addition to the pay that comes directly from Instacart (most people report an average earnings rate of $15 per hour).
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.