The same builder must have done the Sudden Valley house (see Blog 6/27/13) because he used a gas valve instead of a full port water valve.
Not only does it cut the flow to this duplex, but look at the second picture. See the dirty water? That's from restricted flow! It cleared up after a few minutes at full pressure, but think of the poor water quality caused by poor workmanship.
Ball Plumbing's plumbers corrected all the problems, of course, for a lot less than you'd think for the amount of quality we gave.