Woodswitch, this is our old homemade one. (sorry for the bad picture) I don't know if you can see it, but the fire box is on the end. It has wheels on one end and a bar/handle on the other so we can wheel it around the yard.
The chimney has a hinged metal plate to adjust the temperature and to close when not in use. Same with the fire box.
It's 20 years old, I would make a few changes to it if I were building a new one.
It has notches inside to raise and lower the grill, but sometimes I want to raise it when I'm in the middle of cooking something and it's just too much of a hassle to reach in and raise the grate while cooking.
My other complaint is that the lid is pretty heavy, I can open it with one hand, but it sure would be nice if it had a counter balance weight to help lift it.
We use this both as a smoker and just to grill. It has another removable rack in the bottom to set coals on. This one is big enough to cook a 75lb pig.
Overall we do love this thing, it will last forever.
edited to add......the inside grate is in two pieces, I like this because I can remove one grate, slide the other to the middle of the grill, put coals on both ends and slow cook or cook with indirect heat...small things like turkeys, chickens, briskets, without using the firebox at all.