I must admit that I have never heard the phrase used as a generic "transformation"; only ever to describe the move from the rat-race of the city to relaxed sea-side living (most commonly applied to middle-aged couples who move once the nest is empty). The general meaning may well have been (mis-)appropriated by the real-estate industry for all I know. However, I suspect many people would think the general meaning of transformation derived from the concept of a drastic change of lifestyle. cf "tree-change"