I was charged $400+ for a FPV system and install on my DJ Phantom. I was okay with the price..until I got my drone back from them.
These guys are a joke. Typically, an FPV system is installed by going into the drone and adding some simple wires to the main board for FPV video output and power to the fat shark system.
These guys - the actual owners of the company (brothers I believe) - were afraid of doing that I suppose. They installed everything on the outside of the drone along with a HUGE bulky battery that wasn't even needed (YOU ARE SUPPOSED TO GET POWER FROM THE MAIN BOARD/BATTERY).
They even had the audacity to charge me for the external battery and an additional charger needed to charge it every so often.
Do yourself a favor when it comes to your drone repair or needs - RESEARCH the repairs yourself, buy the parts online and do it yourself. OR contact DJI because surprisingly they are helpful (no matter how many times Friendly's tries to tell you they are not).