Never pay up front. Some companies will ask you to pay a small fee up-front for access to survey lists, which is absolutely unnecessary. Check Terms and Conditions, FAQs, or any other area on a survey company’s page containing information on how the company operates. (If such information is hard or impossible to locate, consider it a red flag and cross that site off your list.)
But don't make the mistake of thinking this will be a passive source of income—you're on call whenever you have a guest and you'll always need to keep the place clean for incoming visitors. On top of just renting on Airbnb, consider offering your guests paid add-ons, like Lauren Gheysens', Royal Day Out in London, England—where she gives visitors a local's only tour of the city, complete with bespoke 18th century costumes.
Research other listings in your city on AirBnB and see what the going rate is for a place like yours. You could also just rent out a private room as well or even a bed in a shared room. In fact, that's how AirBnB got its start. However, you might find it hard in the beginning without reviews, but as long as you take really good care of your guests and provide a lot of value, the reviews will eventually come rolling in.