Gibbo, nice idea but i would avoid, I am a member of the bmfa and have qualifications in model aircraft flying, since this drone "craze" the CAA and bmfa have put huge constrictions on flying them i.e max height 400ft (so no dreams of cloud flying or ufo hunting), not near public place,if using fpv a mate has to have a master control to take over at any point. otherwise your liable for lot of lot of damage etc, and dji "fantastic" gps go home system tend to send them somewhere else and loses your £800 bucks along with your go pro camera. i would stick with cheap drones with hd cameras for the fun element. i.e 2-400 pounds.
I have seen no end of lost adverts which go as follows, " reward £100 lost model drone DJI make with go pro camera, was meant to return home but will be somewhere in the nottingham area. what tends to happen is some one who finds it , checks ebay and sell it.
you would also have to educate the buyers on li-poly battery and very real fire hazards ( i.e petrol in your living room type level) ,this only learnt as part of being in a club and having years of experience with electric r/c aircraft, i introduced electric aircraft to most my clubs when they were still fixeated on glow engines and glow was best.
sorry to be the bearer of doom and gloom , however you probably would gain more negative press than positive on this venture.
i would however reccommend the cheap quads with hd camera ,bubble gun,water gun, evac attachments, therre gggrrreat. and only £50