John Grabowski wrote:

Any random thoughts on the subject would be appreciated.


*I would think that some engineering would be involved to determine
the actual soil conditions that caused the problem to begin with. Was the
house built on backfill or sandy soil? Maybe there is an
underground stream which caused some erosion. I would talk to several
contractors on the problem and their methods for correcting it. I
don't think that this is a process that you want to go through more
than once.

Right. The house is in a sub-division with, evidently, problematic soil
conditions as evidenced by the neighbors also having to take remedial steps.

You may have heard the story of the ancient philosopher who said "The earth
is suspended on the shoulders of the great Atlas. Atlas himself is standing
on the back of a great turtle. And before you ask, it's turtles all the way
down."

Here, it's clay all the way down.