Kite- Never ever more than 1000$ no matter what size or brand
Board- This is a tough one TT-100-200$ Surf 300$-600$ Foil complete 1000-2000$ real price should be under a grand once the R&D wears off on wing development.
Control Bar-300$ max
Harness-100-199$ they last forever so could go more.
I can appreciate the quality of good gear. The problem I have with it. Kiting has the most highly depreciative gear you will ever buy (current year and retail)! The sewing is impeccable and the layout if you look at these things is amazing but at the end of the day its a tent with a condom stuffed inside. It wears out quick from sun and the elements. Bars and lines die as fast as the kite no matter how nice and meticulous you are with your gear.
I guess if i were to complain it would be solely on the kites and bars which if you do your homework you can keep the costs down. The rest of it should be probably higher cause its usually a 1 time purchase or once every 5-10 year purchase.
On the flipside of this is what other sport is actually cheaper then kiting? dirt biking, mountain biking, wakeboarding, golf, skiing? the per session use is actually a fraction of the cost of any other sport. its just tough for a newbie contemplating the sport laying down the cash and following through with the sport to get to a level that can enjoy the awesome gear that is out there. I can remember 13 years ago when learning that nothing would stop me from learning how to kite if you have that kind of attitude with it kiting will pay off immensely sadly its too much for most to put the time in. Thus the higher prices