Many paid survey panels offer rewards for referring your friends. Help your friends make money online and do paid surveys together. Another reason to refer a friend for paid surveys is because a lot of paid survey site have a set amount threshold that must be reached before you can make a withdrawal. If you are a few pounds away from reaching the withdrawal threshold you can refer a friend to bump you over the limit.
He is also diversifying his investment portfolio by adding a little bit of real estate. But not rental homes, because he doesn't want a second job, it's diversified small investments in a mix of properties through RealtyShares (Fundrise if you're not an accredited investor). Worth a look and he's already made investments that have performed according to plan.
Paid survey site companies invest billions of dollars into marketing research online. They always want to find out more intricate details of a consumer's relationship with their product. Whether it's a new television show or just an existing product line, companies like Disney, Samsung, and Sony go to great lengths to find out their ideal audiences.