Things to consider

Many people have asked us how we are going to finish the walls, which does present several options. To begin with, you must remember that in the price of the container there comes a complete structural framing system, which will stand alone. Therefore, with any wall treatment or finish that you may consider, you should also think about whether or not it would require "furring out"or not in order to be able to apply that treatment. If you must, then you may be using the same amount of lumber that you would use in a conventional framing system, thereby negating any savings that may be afforded by the container's structure. In addition you must also consider electrical wiring and placement of plug-ins and switches. Therefore, you might simply paint an interior wall, which costs nothing extra, really. Or you might apply an earthen plaster, or a lime based plaster, which might require you to provide some sort of attachment points, such as some screwed on tabs, or just screw tips, or some attached chicken wire, etc., again, a thing that you would probably have to do in a conventional setting.
If you wanted to apply for example, wainscoting, you could screw on a couple of 1x4 strips to attach to, and the same would go for Sheetrock - both of these being some additional input, but minimal. Adhesive could be used, but it might involve an input that could be toxic, depending on the type of glue.
Those are just some of the the thoughts that we have had as we have considered what we will do with the container walls that are exposed inside the house. I say that because some will be covered by kitchen cabinets, and some with bookshelves, and some with adobe, and some (in the bathroom) being necessarily built as dividers, or plumbing walls, thereby substantially reducing the number of walls to be finished.
Enough for now. Exterior walls require other ideas.