The only legit thing I can think of is selling stuff off Craig's List or on eBay if you have things worth any value. But if your 'hood is not safe, then forget Craig's List as you'll be preyed upon for scam, robbery, or even worse. Check eBay's age policy on having an account for selling. Also keep in mind they take a % of your selling price and you are on the hook to pay for shipping unless you include shipping in your selling price (and let that be known in your item description).
You'd be surprised what people will buy out there like old computer hardware, game consoles, etc. Even clothes if they are a designer label and in good condition. For example, I've had an offer for my 25-year old original Sega Genesis and games for $100...