On one recent inspection we spotted a spherical bulge in the gray pipe (at left) which indicates that there is incoming lead water piping. Lead piping is a big deal because lead in the water is a known health hazard. The client, who was intending to purchase the property as an investor home, was unfamiliar with lead piping and was thankful we were able to point that out.
In fact, the plumbing system is one of the major systems in any house or commercial building that we always look closely at, and not just for lead piping. Older structures may also have galvanized pipe (see the second photo) which rusts and corrodes from the inside out. So when we inspect them, we look out for these pipes and point them out as they typically are in need of replacement.