Admittedly, one of the joys of doing Feng Shui is the sense of solving a mystery: Why are people experiencing this? What happened here? What story is the land trying to tell? To really find this out, a site visit is by far the best way, but you can tell a lot from afar as well, say by maps, Google Earth and photographs. Take this picture for example:
Immediately one can assume that the house is unoccupied, rather obviously by the proliferation of plant growth. That assumption could be incorrect though - maybe the resident only uses the back door, or really likes poppies? Feng Shui could actually be more useful in this case. What the entrance tells me is that certainly there's a blocking of ch'i by the proliferation of plant growth, whether or not someone actually lives there or not. That it's poppies implies an association with sleep and forgetfulness. The number 14 is 5 numerologically (1 + 4 = 5), the number of freedom and creativity, also danger. The white entrance is Metal, associated with grief, letting go and value. From the shortness of the shadows it looks like the picture was taken at midday (which it was), and therefore the door must be facing south-west, the 'devil's back door' in Feng Shui, and one of the most challenging directions with which to work. It is also the direction associated with relationships and marriage.
So while no conclusions can be drawn, these are only indications of what might be going on in the house, or have gone on - I sense a freedom and joy that was once present has now gone, due to loss of some kind. Admittedly, that's not much, which is why an on-site evaluation is important, but then we are only at the entrance, at the beginning.