Hi Ken,
My take away from your very first post was that the structure was pre-fabricated and looked like the picture you posted but your recent post states in part "building costs of ~ $40k".
Have you received any estimates yet? I ask as that estimate seems a little high based on pricing where I live (outside of Philadelphia, Pa) and you may be able to afford an alcove which extends to one side where you can put in a bathroom and a small kitchen area (say refrigerator, sink, microwave, etc). Many of the local shed-builders in my area will customize their existing designs (including adding insulation, electric and plumbing).
I'm going off the pricing a friend of mine received on a "she-shed" he had built for his wife.
You have, however, not mentioned two critical design elements - installing cup holders and remote holders along the facia of the layout. 
-Greg
