When an emergency arises with your pipes at home, there is no time to "shop around" for plumbers, get estimates for the specific task needed and ask your friends to recommend a qualified professional. However, hurried moves can also result in inflated plumbing bills or even sloppy work by an inexperienced plumber who still expects to receive the full pay. There is no textbook approach to negotiating a disputed bill, but as a rule of thumb, you must always take a few minutes beforehand to ask the plumber about his hourly rate and his estimate on the duration of the task and the cost of supplies used.
Ask the plumber to explain how he calculated the amount of the bill. The plumber must break down the rate to his personal standard rate -- which he revealed before proceeding with the task -- and the price of the supplies, which he also revealed beforehand.
Contradict the amount the plumber charges with your own estimates, based on the personal rate and supplies price the plumber gave you beforehand. This way, you can ensure that you have a fair reason for arguing, while determining what you believe to be the fair rate.
Call the customer service department of the plumber's agency to complain about the inflated bill or the low standard of work. If the plumber is self-employed, you can settle the dispute by yourselves.
Offer to pay for the bill at the rate you have calculated or slightly above it. Pursue a monetary settlement with the plumber, as this is the least time consuming -- and even cheapest -- way of solving the issue.
Get an estimate for the job's cost from another plumber to ensure that you have not greatly miscalculated the rate. Another professional's estimate is always more valid than your own and is an important asset when disputing the bill.
Inform -- do not threaten -- the plumber that you are willing to file a complaint with your State Attorney General office, the Federal Trade Commission or the Better Business Bureau (BBB): the Bureau accepts complaints even for non-BBB-accredited businesses. It may sound like an extreme action for a disputed plumbing bill, but it is enough to alarm dodgy plumbers who deliberately aim to overcharge you.
Seek legal counsel if the plumber is adamant about the bill. Again, make your intentions of getting legal aid clear -- so that the plumber may rethink your offer -- before calling a lawyer.