Today, not only do we live in an exhilarating time filled with endless possibilities thanks to technology that we once considered to live in the realm of science fiction, but it's also a period that's deeply steeped in the expectancy of instant and real-time returns. The truth is that you can't get rich overnight. It takes hard work and effort. It takes persistence and massive amounts of action. It takes seeing things through and pushing past failure, even as much as you want to give up and throw in that proverbial towel.
Having your own site to sell gently used handbags is probably going to be a really, really difficult endeavor for what its worth. It will be hard to get enough eyeballs/visitors on those bags to generate enough sales to make you any meaningful income (it’s an incredibly small niche and almost too specific in nature). Not to deter you from the idea completely but you’ll need to commit to several years of patience to really hit a home run in that field.
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 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.
I’m really torn here. As a writer, I sympathize with you. I’ve looked again and again into freelancing, and consistently find that the rates other people are willing to work for make it an insulting waste of my time. (Like, $10/hour is what a 15-year-old babysitter makes, not a professional writer.) On the other hand, you really can’t ask others to not compete with you. On the plus side, in my (limited) experience, you do get what you pay for most of the time. My sister had a less-expensive wedding photographer, and she was definitely less than happy with the results. So …