Here’s the situation. In this house every “visible” pipe location has copper piping. At the water heater, main line coming in. Now at most of the fixture valves they are your typical metal valve, but in this picture is this a possible connection to Polybutylene? Like I stated before as far as lines of visible piping, they are all copper.
I checked their disclosure and they have a NO checked on poly piping in home. Home built in 1991.