I've said this elsewhere in the thread, but putting a small/tiny house on a trailer is a good option and won't drift away (at least not in the foreseeable future since it's on wheels with jacks to keep it in place). I think we've reached a point with composting toilets and grey water where plumbing is not that hard, nor expensive. Yes, you still need a water source, but running the actual plumbing lines is low-cost and as long as you're willing to use a composting toilet (no plumbing lines for that obviously) and make use of your grey water in/around your property (which in a lot of the western US should be the norm instead of the exception) it's pretty reasonable. Does require a different way of thinking about things and in a lot of urban areas the "state" might have regulations that prohibit some of these things.