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  • Accurate Ratings

    Local companies rated
    Highest in Quality and Helpful Expertise®

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    Researched company reports.
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Barbara Schallau Consumer
Bay Area

Hany Louis CEO/General Manager
The Tile & Grout King Inc.

Jagdish Hegde Consumer

Leigh Bakhtiari President
City Carpets

Cecile Monfort Consumer
San Jose

Mark Corrallo President
All Seasons Construction

Jim Baylor Consumer
Bay Area

Bev Oliver Consumer
Bay Area

Gifford Teeple Owner
A Reliable Handyman

Tami Aviles Consumer
Bay Area

Tommy Herren Owner
The Lighting Geek

Watch this video on the Diamond Certified Resource: the most accurate and trustworthy way to find local companies rated Highest in Quality and Helpful Expertise®.

We’ve all felt the joy of choosing a good local company and, unfortunately, the pain when we mistakenly choose a bad one. The problem is, every company claims to be good, yet despite these glowing claims some provide inconsistent quality while others are downright unscrupulous.

We’ve solved this problem for you with the Diamond Certified Resource. Only local companies independently rated Highest in Quality and Helpful Expertise® earn Diamond Certified. Our rigorous rating and certification process starts with the in-depth pass/fail rating of each company’s customer satisfaction, license and insurances. Most companies can’t pass our rating and earn Diamond Certified, and every Diamond Certified company must continue to deliver on its promises to you, the consumer. That’s why we conduct ongoing customer satisfaction research and credential-based ratings and monitor each company’s performance.

Every Diamond Certified company is backed by our powerful Performance Guarantee, so you’ll feel confident in your choice when you use our always-free web resource or Diamond Certified Directory. If you try unsuccessfully to resolve a disagreement with a Diamond Certified company, our mediator will work with you and the company to attempt to reach an agreement that both parties can live with. If the mediation fails to produce a mutually agreeable solution due to failure of the Diamond Certified company to honor contractual obligations, uphold industry standards or participate in good faith, we will refund your purchase price up to $1,000.

Each time you visit, you’ll see each Diamond Certified company’s Deep Info, including researched company rating reports, verbatim survey responses, essential articles, photo galleries, videos and expert tips. We put all the information you need to choose a company in one place, and no other web page can match this depth of information.

When you choose a Diamond Certified company, you’ll never be fooled by fake or cherry-picked reviews because we survey a large, random sample of each company’s customers by telephone (typically 100 surveys) to get the most accurate ratings and verify only real customers are responding. Company owners can’t cherry-pick by telling friends and selected customers to post 5-star reviews on our site—we don’t allow it.

So, if you want quality, you’ll have confidence in choosing a Diamond Certified company. We encourage you to visit this website on a regular basis to find updated ratings on top rated companies in your area, see verbatim survey responses on each Diamond Certified company, and read thousands of industry-specific expert articles and tips. We care about customer satisfaction, and we care about you. We’re proud to give you all the information you need to choose with confidence.



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Each Diamond Certified Company Report gives you the most accurate and comprehensive Deep Info available for each company. It includes proof of Diamond Certified status, rating charts, verbatim survey responses, essential articles about the company, a capabilities table, a Diamond Certified Video Profile, key photos, company owner expert tip contributions and more. Click on the graphic to learn more


    We survey a large, random sample of each company’s customers by telephone to get the most accurate ratings...


    In addition to providing rating scores for Quality, Intent to Return and Helpful Expertise®, each surveyed customer is...


    You get to see the company in action, meet the managers, and learn as they describe their specialties and customer...


    You can choose to scan or go deep into these five researched articles on each Diamond Certified company: Company...


    Each company’s key info is logically organized within this table. You’ll find this system of display gives...


    Top rated local company owners are experts in their fields, and they’ve written topic-based expert articles and created...


    If a picture is worth a thousand words, how about an entire portfolio? You’ll get a better sense of each company once...


    This is a good place to go if you want to do extra research on a company. Here you’ll find a link to each company’s...

Specialty Spotlight: Stairs Remodeling

Posted on March 21, 2019 by James Florence

A staircase is essentially a practical fixture, but as the home’s central architectural element, it also has the ability to tie things together aesthetically. Perhaps that’s why many homeowners choose to remodel their staircases in conjunction with other home renovation projects. In this article, we’ll take a glimpse into the niche trade of stairs remodeling. Read more

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Posted in: Home Remodeling, Specialty Spotlight

Spring Maintenance for Your Home

Posted on March 19, 2019 by Suzanne Carroll

After being cooped up indoors during a rainy winter, many Bay Area residents are looking forward to spring. But before you start enjoying the longer days and milder weather, it’s a good idea to survey your property to see how it has come through the winter months. It’s time for springtime home maintenance. Read more

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Posted in: Home Maintenance
Tags: , , ,

Video: Does My Tree Have Sudden Oak Death?

Posted on March 14, 2019 by James Florence

Earlier this week, we posted an article featuring five questions you should ask a tree service technician. One of these questions was in regard to tree health, which should be regularly assessed by a professional. To learn about a common point of confusion property owners have about their trees’ health, watch this informative video by James Cairnes, owner of World Tree Service, Inc.

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Posted in: Landscaping Tips

5 Things to Ask a Tree Service Company

Posted on March 12, 2019 by James Florence

Before hiring a company to service the trees on your property, there are several things you’ll need to inquire about, from licensing and insurance to scheduling and payment. However, there are a few questions many homeowners don’t think to ask, but should. Here are five things to ask a tree service company:


  1. How experienced is your team?

When it comes to working with trees, the stakes are fairly high. After all, trees are living things, which is why tree service technicians have more in common with physicians than handymen. That’s why it’s important to hire a tree service company that possesses an adequate level of knowledge and experience in its field. Read more

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Posted in: 5 Things to Ask, Landscaping Tips
Tags: ,

  • Jeff S.

    Verified customer
    Quality 10
    Loyalty Yes
    Helpful expertise Yes

    If you need any plumbing services, I would highly recommend Duncan Plumbing.
    They are very courteous, on time, and they do what they say they are going to do. They charge what they say they are going to charge, never more. Since the first time I have used Duncan Plumbing, I have never used another plumbing service. They have fixed anything I have ever needed the first time out.

    Response to Diamond Certified Company Duncan Plumbing Ent., Inc.

  • Al C.

    Verified customer
    Quality 10
    Loyalty Yes
    Helpful expertise Yes

    They're super reliable, and they totally live up to their advertising. I thought they were fantastic.
    I liked how prompt and professional they were. I was all around happy with them.

    Response to Diamond Certified Company Pipe Spy Inc.


Liam Caldwell is president of Armstrong Carpet & Linoleum Co., a Diamond Certified company. He can be reached at (415) 754-3955 or by email.


Liam Caldwell: Homegrown Talent

By James Florence, Diamond Certified Resource Reporter

SAN FRANCISCO — When Liam Caldwell started working at Armstrong Carpet & Linoleum Co. as a teenager, he hadn’t the slightest notion that he’d one day be president of the company. “I started here when I was 15, working after school and on weekends,” he remembers. “I did everything from making deliveries to binding carpets and making pads. Even after I went to college, I would return every summer and work at the store.”

After graduating, Liam figured it was time to move on to a new career, but a simple phone call disrupted his plans. “I was considering career options when Steve Balestrieri, Read more

Expert tip
Window Coverings That Optimize Light Control
SAN FRANCISCO — There are several factors to consider when choosing window coverings, from style and material to functionality and even safety. However, perhaps the most significant of all these factors is light control. After all, if you have… Read more

Simon Spark is president of Build SF, Inc., a Diamond Certified company. He can be reached at (415) 992-3027 or by email.


Simon Spark: An Artistic Inspiration

By James Florence, Diamond Certified Resource Reporter

SAN FRANCISCO — Simon Spark has always been an artistic person, but he never expected to apply his talents to the realm of residential remodeling. “I started working in the construction field to support myself while attending college, where I studied fine arts,” he remembers. “After graduating, I spent the next 10 years working as a professional artist, doing primarily mixed media sculptures and drawings. Eventually, in my mid-30s, I came to a crossroads where I wanted to start a family and needed a more financially lucrative livelihood. So, I got my contractor’s license and went into business doing residential building and remodeling in San Francisco.”

Today, Read more

Expert tip
The First Step to Starting a Remodeling Project in San Francisco
SAN FRANCISCO — If you own a San Francisco property and are considering a remodeling project, there’s one preliminary step you’ll want to take before getting a contractor involved: contact the city building department to find out if there are… Read more

William Young is owner of Edge Roofing, a Diamond Certified company. He can be reached at (415) 529-6796 or by email.


William Young: A Competitive Edge

By James Florence, Diamond Certified Resource Reporter

SAN MATEO — As a general contractor, William Young had considered getting into roofing for a long time, but he knew if he did, he’d need to find a competitive edge. “More and more, I was coming across projects that required roof work, so going into roofing just made sense,” he says. “Eventually, in 2006, I got my C30 license to specialize in roofing. However, in order to be successful, I knew I’d need a great team of installers, so I sought out roofers throughout the Bay Area who had good reputations. Edge Roofing was built on the knowledge and experience of myself and my team.”

When asked his favorite part of his job, Read more

Expert tip
Why Roof Gutters Are a Worthwhile Investment
SAN MATEO — Roof gutters are responsible for diverting water off of the roof and away from the home. Throughout the San Francisco Peninsula, there are a lot of older homes that don’t have gutters. While these homes may have… Read more

Corey Haney is a field supervisor at STATCOMM Inc., a Diamond Certified company. He can be reached at (650) 988-9508 or by email.


Corey Haney: Playing it Safe

By James Florence, Diamond Certified Resource Reporter

MOUNTAIN VIEW — When Corey Haney was unsure about his next career move, he took a shot at a job opportunity in the life safety industry. “I had been working in concrete construction, but I got laid off when the economy crashed in 2008,” he recounts. “I wanted to get into an industry that was more insulated from economic turbulence, so I started researching. I found an opening with Statcomm Inc. and it seemed like a good fit—not only did life safety strike me as a pretty interesting field, it was definitely more stable than construction. I started as an apprentice, Read more

Expert tip
2 Fire Safety Tips for Your Home
MOUNTAIN VIEW — When it comes to fire safety, even small steps can potentially save your life. Here are a couple of basic fire safety tips for your home: 1. Test fire safety equipment. The simplest way to reduce fire… Read more

Rory Moore is owner of RM Construction, a Diamond Certified company. He can be reached at (415) 534-5497 or by email.


Rory Moore: From the Farm to the City

By James Florence, Diamond Certified Resource Reporter

SAUSALITO — After four decades in construction, Rory Moore reflects on how his upbringing provided the foundation for his later career. “When you grow up on a farm in the West of Ireland, you learn a lot of different trades,” he recalls. “We had to build our own barns, walls, you name it…so it all started at a very young age for me. After I turned 12, I began working alongside my older brothers for a local plasterer during the summers, and things progressed from there.”

Eventually, Rory made his way to San Francisco, Read more

Expert tip
Air Filtration Systems: A Healthy Home Improvement
SAUSALITO — When it comes to home remodeling, most homeowners are concerned with improving aesthetics or performance. While these aspects are certainly worthwhile, an equally important concern is creating a healthy indoor environment. As building code requirements become increasingly focused… Read more

Roee Erenshteyn is CEO of 911 Remediation LLC, a Diamond Certified company. He can be reached at (510) 275-3708 or by email.


Roee Erenshteyn: Getting Acquainted

By James Florence, Diamond Certified Resource Reporter

RICHMOND — When asked how he ended up in the water and fire damage restoration industry, Roee Erenshteyn says it resulted from making an acquaintance that, while remote, was very close to home. “While researching job opportunities online, I got in touch with Erez Gilad, owner of 911 Remediation, via Facebook,” he explains. “We’re both Israeli, and although he lived in the U.S. and I still lived in Israel, we had a lot of mutual connections. After interviewing with him, I started working for his company remotely. In May 2017, I moved to the U.S. to assume the position of CEO.”

When asked his favorite part about his job, Read more

Expert tip
Why You Shouldn’t Attempt to Clean Mold Yourself
RICHMOND — Upon discovering mold in your home, your first instinct will likely be to clean it up yourself. However, in most cases, you’re better off ignoring this instinct and leaving the job to a professional. Why? Because cleaning mold… Read more

Nikolaos Margaritis is president of Kyvos Construction Inc., a Diamond Certified company. He can be reached at (510) 394-4929 or by email.


Nikolaos Margaritis: Building Forward

By James Florence, Diamond Certified Resource Reporter

Before he came to the United States, Nikolaos Margaritis was a building contractor in his home country of Greece. While his relocation initially posed a professional setback, it ultimately set him up for greater success. “I started in construction many years ago when I lived in Greece, and at one point I even had my own general contracting firm,” he recounts. “However, as the situation in Greece began to worsen in the mid-2000s, I made the choice to immigrate to the U.S. Upon my arrival, I got back into construction, but I basically had to start all over again as a laborer. Read more

Expert tip
Preliminary Steps for Hardwood Floor Installation
PITTSBURG — When installing a hardwood floor, proper procedure is critical. This includes preliminary steps like preparing the subfloor and assessing interior climate conditions. Be sure to observe the following preliminary steps for your hardwood floor installation project: Preparation of… Read more

Brian Folden is president of Fireside Property Management, a Diamond Certified company. He can be reached at (408) 498-7959 or by email.


Brian Folden: A Fire Inside

By James Florence, Diamond Certified Resource Reporter

SAN JOSE — Brian Folden has always been motivated by a burning desire for professional independence. While he’s achieved this to varying degrees throughout his career, only recently was he able to fully attain it. “I’ve always felt a drive to operate independently and be my own boss, which is one of the reasons I got into real estate,” he says. “My dad has been in the industry since I was a kid, so I basically followed in his footsteps. After 30 years working in partnership with him at Fireside Realty, I wanted a business I could run on my own. Read more

Expert tip
The Importance of Relational Boundaries in Property Management
SAN JOSE — If you’re a property owner, make sure you’re establishing proper relational boundaries with your tenants. While it’s good to have a healthy working relationship with your tenants, it’s important to avoid getting overly close or emotionally involved… Read more

Duane Vos is CEO of Creative Window Fashions, Inc., a Diamond Certified company since 2011. He can be reached at (415) 935-0986 or by email.


Duane Vos: Blind Ambition

By James Florence, Diamond Certified Resource Reporter

ROHNERT PARK — When Duane Vos started installing window blinds as a young man, he had no idea it would lead to a full-fledged career. “My dad owned a flooring and decorating store in Parker, Arizona, where they sold window coverings but didn’t install them,” he remembers. “He was also into cars and was paying me to restore a ’59 El Camino in the shop behind the store. One night, his manager told me he’d been installing blinds after work for the last 15 years and asked if I was interested in taking over for him. At $15 per blind, Read more

Expert tip
The Value of Window Shutters
ROHNERT PARK – When it comes to selecting new window treatments, today’s homeowners have numerous options. However, out of the many choices available, only one will substantially add to the value of a home: shutters. Once they’re installed,… Read more

Francisco Cortes is president of Green Environment Landscape, Inc., a Diamond Certified company. He can be reached at (408) 372-7932 or by email.


Francisco Cortes: Always Growing

By James Florence, Diamond Certified Resource Reporter

WATSONVILLE — After embarking on a career in landscaping, Francisco Cortes charted a professional path marked by continual growth and development. “Before I got into landscaping, I was working in a warehouse and wanted a job where I could work outside,” he remembers. “A friend suggested becoming a landscaper, and after looking into it, I decided to give it a shot. I really enjoyed landscaping work and decided to take some college courses to learn about landscape design and irrigation. Several years later, I became interested in hardscaping, so I joined the California Landscape Contractors Association so I could learn more about that aspect. Read more

Expert tip
3 Tips to Conserve Water in Your Yard
WATSONVILLE — When it comes to irrigating your yard, small steps and smart practices can go a long way toward conserving water. Consider the following tips: Water less often for longer intervals. Many people water their lawns and gardens every… Read more

Daniel Gagne is a lifetime veteran of the plumbing industry and owner of Benjamin Franklin Plumbing, a Diamond Certified company. He can be reached at (415) 788-4357 or by email.


Daniel Gagne: Plumbing Pride

By James Florence, Diamond Certified Resource Reporter

NOVATO — When Daniel Gagne began his plumbing career, he had no idea of the level of success he’d one day attain. “My dad was a plumber, so I was introduced to the trade at a very young age,” he recounts. “After high school, I worked for the family business for a while, and after doing some traveling in my 20s, I ended up in Marin County, where I got a job with a local plumbing company. In 1996, my brother and I co-founded our own plumbing business, which focused on new construction and remodeling work in Marin, Napa, and Sonoma Counties.”

Three years into their joint venture, Read more

Expert tip
DIY Water Heater Maintenance
NOVATO — A crucial aspect of plumbing system maintenance is to drain your water heater’s tank at least once a year. This is important because of all the sediment in the water, which tends to collect and sit at the… Read more

Bo Posey is a lifetime veteran of the automotive industry and president of Metric Motors, a Diamond Certified company. He can be reached at (707) 206-7356 or by email.


Bo Posey: An Early Fascination

By James Florence, Diamond Certified Resource Reporter

SONOMA — Even from a young age, Bo Posey seemed destined for a career in the automotive industry. “My dad was a machinist and always did his own car maintenance, so I was introduced to automotive work early on,” he recounts. “I’ve always been fascinated by cars. Even before I started working on real ones, I was fixing remote-controlled cars for kids in my neighborhood.”

As soon as he was of age, Bo dove headfirst into a professional automotive career. “Right out of high school, I began working as a mechanic for a trucking company, maintaining and repairing big rigs. Read more

Expert tip
Turbocharged Engines: What You Need to Know
SONOMA — In recent years, more and more vehicle manufacturers are incorporating turbocharger technology into their engine designs. A turbocharger utilizes exhaust gas to pressurize the air inside the engine, which enables the engine to take in more fuel. With… Read more