Unless I'm missing something, the whomping lease cash deals are not available anymore. At least not visibly upon a cursory glance at kia.com with my zip code plugged in. That could put a damper on the early buyouts if accurate.
To take advantage of Kia's lease incentive/rebate, you lease in the first place. Then, to save thousands in lease rent over the course of the total payments, you do the buyout. Obviously, the fewer monthly payments you make before the buyout, the fewer rent payments you make as well. By doing the buyout in only three months, I saved well over $5K in lease rent.