I operate a small RC heaven. With 13 heli's ranging up to the Trex700E to my 31 quads/UAV's/Drones ranging in size up to a 950mm octagon.
I buy, sell, repair, and junk RC items. Love the hobby and have been able to finance everything through my little shop and have even made a profit now and then. I'm not into this for the money although it's nice.
My fleet is still on the rise, time to sell off some before I need a bigger office. Just sold the 950mm oct to a guy in Europe but also acquired some more items.
I build/sell custom quads. I buy the frames from distributors and then set them up with electronics to be BNF and promote this hobby through a local club where I offer my services for free.