Owning a “real” business means you need to think about bank loans or financing, leases, maintaining inventory, business insurance, finding staff, training staff, etc. You then need to factor in finding a prime location for your business. If you don't have enough footfall then you can expect to be shutting up shop in as little as a few months. In fact, 50% of small brick-and-mortar businesses fail within their first 3 years.
Sell scavenged valuables. If you have a metal detector, or even just a good eye, go to public places where people are likely to drop something unnoticed (such as parks, beaches, and shopping areas), and look for money, jewelry and other valuable goods. This method isn’t very reliable, but you just might get lucky and be able to find something you can sell quickly for cash.
Now, here's an online business model that has unfortunately become the butt of far too many jokes. This is because a certain segment of society (that’s you, hipster!) went around loudly telling anyone willing to listen that they were full-time bloggers. The net result of all this misplaced enthusiasm is that if you tell any of your friends or family you're going to start a blogging business, they'll wrinkle their collective noses at you, while coughing politely.
Be a private cab driver. Companies such as Uber and Lyft have set up services that connect drivers with people who need a ride and are willing to pay for it. In order to take advantage of this opportunity quickly, you must own a car, have a valid driver’s license, and meet other qualifications. It might take a little bit of time to get registered as a driver with the service, but once you are, there are opportunities to make money fast because these services are in high demand.