1. Observe and protect
Write down what’s happening, stop it from getting worse if that’s safe, and pull together any history on that fixture or line.
2. Evaluate the house and site
A real diagnosis looks at how the fixtures are behaving, what the pipe is made of, pressure, drainage, venting, shutoff locations, access, and past work.
3. Define a written scope
Get it in writing — prep, protection, materials, access, permits, testing, cleanup, restoring finishes, exclusions, and how changes get handled.
4. Compare providers
Check credentials, then compare the thinking behind each bid — not just which number is lowest.
5. Inspect closeout
Before it’s done, confirm what was tested, that cleanup happened, get the paperwork and warranty, and know what’s still on you to maintain.