I have bought this to build a Quad one year back, flown for couple of times and moved to RTF.
100% Functional with all the features, Money return Guarantee for 15 days (time sufficient to build and test) .  Also available is Data Link (Brand New never used)

Zero UAV YS-X6 Kit (Asking Price 17,500) (Hong Kong price US$500)
1) Flight Controller
2) IMU
3) GPS cum Compass
4) Wifi Unit
5) LED
http://hobbyking.com/hobbyking/store/__25925__ZeroUAV_YS_X6_Autopilot_GPS_Flight_Control_System.html?strSearch=ys%20x6

Data Link (Asking Price 11,000) (Hong Kong Price US$250)
1) Transmitter
2) Receiver
3) Antennas for the above
http://hobbyking.com/hobbyking/store/__67759__Zero_Tech_Data_Link_900mHz.html?strSearch=zero%20data%20link

* DISCOUNT 20% LESS IF YS-X6 + DATA CONTROLLER PURCHASED TOGETHER.
* 10% ADDITIONAL DISCOUNT FOR COLLEGE STUDENTS IF YOU ARE ACTIVE ON RC-INDIA SINCE AT LEAST 2 YEARS.
* LOOK FOR QUAD HARNESS WITH MOTORS & ESCs LISTED ON RC-INDIA, BEST SUITABLE WITH ABOVE COMBINATION GOING CHEAP.