If you can find and restore items like furniture and appliances, you can make a substantial amount of money. You can acquire the items on Craigslist, or even at garage sales or estate sales, restore them, and then list them for sale on the site. You may also be able to market certain items on eBay, particularly if they are small, unusual, but high in price.
Sites like CookApp, Cookening, EatWith and MealSharing are to restaurants what Airbnb is to hotels. Sign up as a host to earn dough by cooking and serving a meal to guests in your home. It's up to you what you want to cook and how many people you can accommodate. Cooks are paid directly through the site, so no cash ever changes hands. Earning potential: $50-$100 per meal
If you have a good idea for an app, and the skills to create it, then producing your own premium app can be profitable. However, with so many free apps available, it may be hard to convince people to pay. If you want to go down the premium app route, consider having a basic free version to encourage people to download the app in the first place. You can then provide the option of upgrading to a premium plan once users realize how useful the app is.