I'll never go with Pete the Plumber again.
Years ago, I did a paid consultation for a viability study for getting a residential tankless gas-powered water heater installed .
The crew that came down took the measurements, then left, telling me I'd get my report within a couple of days.
A week later, I phoned, as I still didn't have the report.
I was told that the report was not written because the measurements had been lost.
When I asked them to come back and redo the survey and measurements, I was told that I'd have to pay for the company representative to come back because he was redoing his work.
Instead, they pulled numbers out of the air, and gave me a bunch of hand waving.
So, I told them no.
My final recommendation, that I've been telling everyone that asks (for decades) is, "Don't hire Pete the Plumber. They're unprofessional and untrustworthy. Hire anyone else."