It has already gone wrong
Start with the plumber in writing, keep every record, and only then move up to a board, a card dispute or a court.
Updated .
These seven decisions are general information, not legal advice. The routes differ by state, and each page names the place each rule comes from.

- Call the same plumber back or hire someone new?
- Call the same plumber back: recent work, clear fault, money still unpaid
- Hire someone new: urgent damage, no reply, or trust is gone

- Complain to the company, the board or the attorney general?
- The company: every dispute starts here, while a fix is possible
- The licensing board: license problems, skipped permits, conduct on the job
- The attorney general: deceptive dealing, or a firm that ignores you

- Small claims court or a lawyer?
- Small claims court: loss under your state limit, simple facts, good paperwork
- A lawyer: loss above the limit, a lien, or a disputed contract

- Dispute the charge or pay and argue later?
- Dispute the charge: credit card, unsettled balance, firm stopped helping
- Pay and argue later: small amount, non-card payment, or card route closed

- Lien notice: pay it or push back?
- Pay it: the debt is real and a signed release comes with payment
- Push back: already paid, wrong amount, wrong job or bad work

- Cancel the contract or keep it?
- Cancel the contract: signed at home recently, doubts, deadline still open
- Keep the contract: you asked for it, fair price, complete papers

- Post a review now or after it is settled?
- Post now: firm has gone silent, facts are documented, others could benefit
- Post after it is settled: talks are moving or a fix is booked
