Why the same spot matters so much
A before and after pair only works if the two frames are the same frame. Stand in one place, note what is beside your feet, and go back to that exact place for the second shot. Same spot, same height, same direction, same framing, and as close to the same time of day as the job allows.
A pair shot from two different angles proves nothing. The reader cannot tell whether the yard changed or the camera moved, and an honest pair shot that way still looks like a trick, so you get no credit for work you really did. Light matters for the same reason: bright sun in one frame and flat cloud in the second reads as two different yards.
The practical version on a job is simple. Take the before shot from the sidewalk or the far curb before anything comes off the trailer, because once the crew starts there is no going back for it.