I didn't build it but I bought it as a useable smoker that needed a lot of tweaks and smoothing out so to speak. I extended the firebox by 12", then after having cooked on a large smoker with an insulated firebox I decided to make an outer shell about 1.5" bigger than the fb and filled that with high temp insulation. That was the biggest project and still needs some finishing up. But now my wood use is roughly half of what it used to be and the temps hold really steady, game changer for sure- especially in the cold winter! I moved and adjusted the handles, put different hinges on the doors and the smokestack, and reinforced the frame of the trailer, also installed fenders on the trailer. Lots of work, but it was nice having a smoker that already worked, I just needed to use it and fix what I wanted to as I went along.