Brake controller for towing with X1

[phrench]

I’m buying a small camper <2500 lbs. I have a Curt class 3 hitch, and 4 pin wiring on my 2012 X1. Has anyone successfully installed a brake controller and 7 pin trailer wiring? I have 2 Tekonsha brake controllers sitting in the garage as well. I have been scouring the web for this info. I have put over $2K into the x1 in the past year, and now I’m contemplating dropping another $7K- $8K to move to an X5. I have read a number of stories about small Airstreams and other campers being towed by X1’s and like the idea of small car with small camper. Any help is appreciated. Thanks