Free: Contests & Raffles.
One other thing I saw a lot when doing my own research was the value of a larger size. For instance, a medium Seek Outside stove may be so many ounces lighter but your burn times go way down with less volume. So most people seem to go with a large for the best compromise between weight and burn time. You can also save some weight by going with a smaller diameter stove pipe. Seek's U-turn stoves use a 2.5" diameter which is 1.5 oz/ft vs the regular stove pipe which is 3" diameter and 2 oz/ft.
My Seek XL will hold coals for 2 to 2 1/2 hours hours packed with 4" logs. But that will run you out of a teepee unless really cold out.