1. Observe and protect
Document the symptoms, limit further damage if it's safe to do so, and collect any relevant history.
2. Evaluate the house and site
A workable diagnosis takes stock of fixture behavior, pipe material, water pressure, how drainage and venting are laid out, where the shutoffs are, how accessible the work area is, and what repairs have already been made.
3. Define a written scope
A written scope should clarify preparation, protection, materials, access, permits, testing, cleanup, finish restoration, exclusions, and change-order handling.
4. Compare providers
Verify credentials and weigh the reasoning and boundaries behind each proposal, not only its bottom-line total.
5. Inspect closeout
Confirm testing, cleanup, documentation, warranty terms, and any remaining maintenance duties before closing out the job.