KitHAUS makes kit structures like this one with a bolt-together aluminum frame and SIPs floors, walls, and ceiling.  With 117 square feet, the kitHAUS K3 is being used on a Shea Homes project in San Diego as a leasing office, though it could easily be used elsewhere as an artist studio or home office.  A Halcyon model mini-split from Fujitsu cools the space, which costs about $40k with decks and accessories (but not the mini-split).

[+]  More info on the K3 module from kitHAUS.

Credits: kitHAUS.