I started it August 29th and completed Oct 30. The walls are 7'4" at the wall going to 8'2" in the center... The model I got came from Tuff Shed. It is 12 x 16'8" ( 200 SF ) the max that the city would allow. It does have a concrete foundation.
Photos and discussion here. One interesting part of the discussion is the guys like the smaller size. We see lots of super-large shops featured in magazines. This one looks like it would be comfortable to actually work in.