We are nearly finished transforming a shipping container into a 2 bedroom, kitchen, bathroom bunk house with a separate office for the farm. Although we have considerable mechanical systems (solar thermal, graywater treatment, composting toilet), the benefits of the shipping container is that you can drop it onto your land and it comes completely weatherproof. It will take quite a lot to heat it as is, but you can slowly insulate the inside and not worry about the weather. Come spring you can start cutting out windows and doors. All that is needed is an 8 -foot timber on one end and an 8-foot at the other end 40 feet apart. Pretty simple foundation. If this is intriguing, I suggest getting the undercarriage spray-foam insulated while in transit - we had the container placed atop two others to easily access the bottom for the foam insulation. Some spray-foam materials are more kind than others,. so you should do your research, unless you are on a tight schedule, then use what's available. Insulation is the cheapest element of the process that has the most benefits. Don't skimp on it.