Does he want a great camera?. Any specific requirements he has, then i can tell better?
Try live demo of OPPO F1. Its both cameras are too good for its price and lots of useful gestures and controls for great photos. Performance is solid.
You can get it used in ~18000 with warranty. Its released few months back, so you will get 3-4 months old phone at max. Oppo has its own company warranty, not distributor warranty like Greentech, M&P, Airlink warranty etc, so after sales services are very good.
https://www.youtube.com/watch?v=bWuToNEFrIE