Flip old electronics on ebay, a laptop or something pieced out is generally worth more than what it costs sold whole. I also flip clothing every great once in a while from a local discount store, the catch is they sell these things super moldy/stained/dirty to the point they couldn't sell it in some states, so I have to do diy drycleaning for example on suits and hope it works. I also sell baked goods in small batches (cakes are especially a crowd favorite like chocoflans), don't need a food license then, helps if you have a captive audience like a class or workplace you can bring the goodies in, have to invest a little in dropping the treats off for free first so they can get familiar with what you can make. If you have family or something in these scenarios they can help drop off the baked goods.
Before they switched the trash system on trash day it was worth joining up with someone that has a truck and beating the trash truck to people's dumped furniture etc treasure then flip that on marketplace, craigslist etc.