If you're ready to enter the ecommerce fray, you could sell your own stuff. Of course, along with selling your own stuff on your own website comes a whole slew of both responsibilities and technical configuration and requirements. For starters, you'll need a website and a hosting account. You'll also need a merchant account like ones offered by Stripe or PayPal. Then you'll need to design that site, build a sales funnel, create a lead magnet and do some email marketing.
Even if it’s a mundane task like walking dogs, you could start the next (or only) full-service dog walking and grooming service in your town (where dog owners rave over your business and always refer you to others). You can also hire other dog walkers as you grow, and turn your side hustle into a sustainable enterprise. You just have to do the work, and do it well.
You could easily do home organizing for people, an industry that has gained a lot of popularity since the debut of Netflix's hit series Tidying Up with Marie Kondo. If you're a tidy and organized person yourself, and you're good at organizing spaces, why not offer your services to people around you? You'd be surprised at how many people, even on your own social media feed, might take you up on doing something like this.
High-ticket consulting or coaching: You could sell your own high-ticket consulting or coaching products from your website. You'll still need a website, merchant account, sales funnel, lead magnet and many other items. But you can easily earn a substantial amount of money from each individual customer, making it well worth the arduous setup required.