I did it myself, so easy. And I am not a car guy. The consumer product like Avalon King is very easy to do, everyone can do it.
It lasts about 2 years, vs the prod shop 5 years as they claim. Yah, the pro shop might have a little better result and last longer since they use professional-grade, but it will cost you. I am very happy with my DIY result, car shines like WAX.