Hiring a plumber you have never worked with before is a bit of a leap of faith, unless you know what to ask.
Most people get one or two quotes, look at the price, and make a decision. Price matters, but it is not the only thing that matters. A low quote from a plumber who skips permits, sends unlicensed subcontractors, or disappears when something goes wrong is not actually a good deal.
These ten questions take about five minutes to ask and tell you most of what you need to know before committing to any plumbing job. A plumber who is worth hiring will answer all of them without hesitation.
Ready to work with a plumber who can answer yes to every question on this list? Call AYS Plumbing & Rooter at (909) 316-3535 or request an appointment online.
1. Are You Licensed and Insured in California?
This is the first question, and it is not negotiable. California requires plumbers to hold a C-36 plumbing contractor license issued by the Contractors State License Board. That license means the plumber has passed a trade exam, meets experience requirements, and is registered with the state. You can verify any California contractor license at the CSLB website using the license number.
Insurance matters just as much. A plumber working in your home without general liability insurance means that if something is damaged during the job, you may be the one paying to fix it. Workers compensation insurance means that if someone is injured on your property, you are not exposed to that liability either.
Ask for the license number and the name of their insurance carrier. A legitimate contractor will provide both without any hesitation.
2. Do You Pull Permits for Work That Requires Them?
Permit requirements vary by job type and city, but in Upland and Ontario, many plumbing jobs including water heater replacements, sewer line repairs, and repiping work require permits. A permit means the work gets inspected by a city inspector who confirms it meets code.
A plumber who skips permits is saving time and paperwork at your expense. Unpermitted work can create problems when you sell the home, complicate insurance claims, and leave you without any official record that the job was done correctly. If a problem develops later, you have no documentation to fall back on.
The right answer to this question is yes, we pull permits for any work that requires them, and the permit cost is included in the estimate. If a plumber suggests skipping the permit to save money, that’s a reason to keep looking.
3. Can You Give Me a Written Estimate Before Work Begins?
A verbal quote is not a quote. Before any work starts, you should have a written estimate that specifies what is being done, what materials are being used, what the labor cost is, and what is not included. That document is what protects you if the final invoice looks different from what you were told.
Pay attention to how the estimate is structured. A detailed estimate that breaks out labor, materials, permit fees, and any contingencies is a sign of a plumber who manages jobs with care. A single line item with a total number and no breakdown is harder to hold anyone accountable to if something changes.
Ask specifically whether the estimate is a fixed price or an estimate that may change. For straightforward jobs, a fixed price is reasonable to expect. For more complex work where unforeseen conditions are common, an honest plumber will explain what could cause the price to change and by how much.
4. What Does Your Warranty Cover, and for How Long?
Any plumbing job worth doing comes with a warranty on workmanship. The question is what that warranty actually covers and for how long.
Workmanship warranties typically cover defects in the installation itself, meaning if something was done incorrectly and fails as a result, the plumber comes back to fix it at no charge. Most reputable plumbers offer a workmanship warranty of at least one year on standard repairs. Larger jobs like repiping or sewer line replacement may carry longer warranties.
Parts and equipment also carry manufacturer warranties that are separate from the workmanship warranty. Ask whether the plumber registers the equipment warranty on your behalf or whether that is something you need to do yourself.
Get the warranty terms in writing. A warranty that exists only as a verbal promise is not much of a warranty.
5. Do You Have Experience with This Specific Type of Repair?
Plumbing covers a wide range of work, and not every plumber has deep experience with every type of job. A plumber who is excellent at fixture repairs and drain cleaning may have less experience with trenchless sewer repair, whole home repiping, or tankless water heater installation.
For a straightforward job, general experience is usually sufficient. For more specialized work, ask directly how many times they have done this specific type of repair and whether they can point to any examples or references from similar jobs.
The answer does not have to be hundreds of completed jobs. It does need to be an honest answer that gives you confidence that the plumber knows what they are doing with your specific situation.
6. Will You Be Doing the Work Yourself or Sending a Subcontractor?
Some plumbing companies function primarily as scheduling operations. They take the job, price it, and then send out a subcontractor to do the actual work. That subcontractor may or may not have the same level of licensing, insurance, and experience as the company you hired.
This is not automatically a problem. Many large plumbing companies use subcontractors effectively and maintain quality control across their network. But you have a right to know who is showing up to your home and whether they are employees of the company you hired or independent contractors.
Ask whether the person doing the work is a company employee or a subcontractor, and if it is a subcontractor, ask whether they carry their own license and insurance. If the answer is vague or evasive, take note.
7. How Do You Handle Unexpected Costs if the Job Turns Out to Be More Complicated?
Plumbing often involves opening walls or accessing pipes that have not been seen in years. Sometimes what is found is more complicated than what the original estimate assumed. How a plumber handles that situation tells you a lot about how they operate.
The right answer involves a clear process: they stop work, show you what was found, explain why it changes the scope, and get your approval before proceeding with anything that adds to the cost. You should never receive a final invoice that is significantly higher than the estimate without having been consulted and given the opportunity to decide how to proceed.
A plumber who says unexpected costs just get added to the final bill without prior notification is one to approach carefully. Ask specifically what their process is and what you should expect if something unexpected comes up mid-job.
8. Can You Point Me to Recent Reviews or References?
Online reviews are one of the most practical ways to get a sense of how a plumber operates in the field. Google reviews in particular reflect real customer experiences and are difficult to fabricate in volume. Look for patterns across multiple reviews rather than weighing any single one too heavily.
What to look for: consistent mentions of showing up on time, communicating clearly, pricing that matched the estimate, and quality work that held up after the job was done. A high volume of detailed positive reviews over a sustained period is a stronger signal than a handful of five-star ratings with no written content.
You can also ask the plumber directly for references from recent jobs similar to yours. A plumber with satisfied customers will have no hesitation pointing you toward them. Read what AYS Plumbing & Rooter customers have to say before making your decision.
9. What Does Your Cleanup Process Look Like When the Job Is Done?
A plumbing job that leaves the work area cleaner than it was found is a sign of a crew that takes pride in the work. A job that leaves debris, old materials, and a mess for the homeowner to deal with is a sign of the opposite.
Ask specifically what gets cleaned up and hauled away after the job. For jobs that involve opening walls or excavating the yard, ask what the site looks like when the plumber leaves, and what follow-up work, if any, is the homeowner’s responsibility. A haul-away of old equipment, such as a water heater or sections of old pipe, should be included in the scope of work. If it is not, ask why.
This question is easy to overlook when you are focused on the repair itself, but the answer reveals something real about how a plumber values your home and your time.
10. How Can I Reach You if There Is a Problem After the Job Is Complete?
This question matters more than most people realize. A plumber who is easy to reach during the sales process and then difficult to contact afterward is a pattern that shows up in negative reviews far more often than it should.
You want to know: is there a direct line to someone who can help, or will you be routed through a call center and put on a waiting list? If something fails within the warranty period, what is the process for getting it addressed and how quickly can you expect a response?
The answer should be clear and specific, not vague reassurances. A plumber who says call us any time and gives you a direct number is making a different kind of commitment than one who points you to a general contact form.
A Plumber Who Answers These Questions Confidently Is Worth Hiring
None of these questions are difficult for a legitimate, experienced plumber to answer. They cover the basics of running a professional operation: licensing, insurance, permits, warranties, communication, and accountability. A plumber who gets defensive, hedges, or cannot give you a straight answer to any of them is giving you useful information about how the job is likely to go.
AYS Plumbing & Rooter is licensed and insured in California, pulls permits for all work that requires them, provides written estimates before any job begins, and stands behind the work with a clear warranty. We serve Upland, Ontario, and the surrounding Inland Empire communities, and our work speaks for itself. Call (909) 316-3535 or contact us online and ask us anything on this list.