Home additions — foundation, bedroom, bath and breezeway builds repeatedly praised
Basement conversions — code-compliant finished basements described across several years
What does a remodeling project cost in Greater Boston?
Typical Greater Boston range for this kind of work, from regional averages — not a quote from Bonsai Builders. Use it to sanity-check bids, then get the real number in writing.
Kitchen remodels — design help and cohesive finished rooms cited often
Permitting handled — homeowners describe town approvals and inspections managed for them
Problem recovery — crews finished kitchens another contractor had wrecked
Daily site cleanup — reviewers note homes left clean each evening
Named crew — Trevor, Kenny, Mike and Dave praised individually by customers
Smaller jobs — a 2023 reviewer says a quote visit was cancelled
Schedule slippage — a 2026 reviewer describes weather delaying parts of a build
Pre-hire five stars — some reviewers praise them without having work done
Second licence — construction supervisor number appears only on a directory listing
Thin BuildZoom score — its 5.0 average rests on one rating
Bonsai Builders is a general contractor working out of 12 Bond St in Spencer, Massachusetts, and homeowners deal with the same two people throughout: Jason and Kristin Hintlian. Kristin is described as a co-owner of the company in a national personal-finance article, and one homeowner in 2025 simply called it "a well-run family business." Its Massachusetts home improvement contractor registration, number 201698, is verified active with the state registry, held in Jason Hintlian's name.
The work people hire them for is substantial rather than small: in 2026 homeowners described adding a foundation, primary bedroom, bathroom, laundry and breezeway; turning an unfinished basement into a playroom, bar, half bath and gym; and replacing an old three-season porch with a larger deck. Kitchens are the other constant — several reviewers credit Kristin with the design and material choices and Jason with the build, and a 2025 customer described a full kitchen demolition and remodel that met its original timeline. Their comment history runs from 2021 to 2026 across seven sources, with nine reviews in the last six months and no negative ones among them.
Two themes recur in a way that is unusual. The first is paperwork: multiple homeowners describe Bonsai handling town permits and building departments for them, including a 2024 project that brought a basement staircase up to code in a tight space and a 2025 first-time buyer whose basement had failed inspection after another contractor's permit was denied. The second is rescue work — two homeowners in early 2026 hired them after another contractor wrecked their kitchen, and both described the repair starting within days. Reviewers also name individual crew members — Trevor, Kenny, Mike, Dave — and repeatedly mention the house being left clean at the end of each day.
What is worth asking about before booking. A 2023 one-star reviewer said Bonsai cancelled a scheduled quote visit two days out, telling them the job was not worth the company's time unless they were willing to spend more — so if your project is small, confirm they want it before you build a schedule around them. A 2026 reviewer on a large addition described weather and sequencing pushing pieces of the job back. And a handful of the five-star reviews come from people who never actually hired them: one wrote in 2026 before any work was contracted, and another in 2025 met the couple repeatedly over a year and then chose someone else.
They are the right call for a multi-room renovation, addition, or basement conversion where permitting and design decisions are part of the job. Before signing, ask them to confirm the construction supervisor licence a directory lists for them, and get the schedule and change-order terms in writing.
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““We’ve worked on projects where properties bought and renovated efficiently have seen ROI percentages between 20%-30%,” said Kristin Hintlian, who’s worked on renovating homes in the area with Bonsai Builders.”
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““These regulations may limit the types of renovations or expansions homeowners can undertake, impacting the flexibility and personalization of the property,” said Kristin Hintlian, co-owner of Bonsai Builders.”
If I could give Bonsai Builders more than five stars, I would. From the very first conversation to the final walkthrough, Jason, Kristin, and their entire team were incredible. They made the whole process feel easy, kept us informed every step of the way, and were always available to answer questions or address any concerns. You never feel like you’re just another customer—they genuinely care about the work they do and the people they’re doing it for.
The craftsmanship is second to none. Every detail was done with care, precision, and pride, and the finished product completely exceeded every expectation we had. What amazed me even more was how quickly they worked without sacrificing quality. I honestly don’t know how they do it. Their team is efficient, organized, respectful, and clearly passionate about what they build.
They took an unfinished basement and turned it into the dream space my family and I will enjoy for years to come. It feels like it was always meant to be part of our home. If you’re looking for a contractor, don’t waste your time shopping around. Bonsai Builders sets the standard for what a contractor should be. They’re honest, family-oriented, incredibly talented, and truly take pride in delivering exceptional work.
This was one of the best experiences I’ve ever had hiring a company, and I recommend them without any hesitation. 1000/10.
Working with Jason and his whole team went very smoothly. Kristen was a big help picking out flooring, tile, cabinets and paint color. (Something I couldn't do on my own). All though the weather threw us some curve balls and organizing a big project like we had done sometimes caused some things to be delayed, everything came out amazing and we are loving the new addition. Thanks Guys!
We worked with Bonsai to add a foundation, primary bedroom, bathroom, laundry and multi- use breezeway space. They worked with our town for proper permits, guided us through the design and build process, and we are now enjoying a great new space. The work is high quality and everyone was consistently professional and responsive. We highly recommend!
We hired Bonsai to transform our unfinished basement into a multi-purpose space, including a large open playroom/bar area, a half bath, and a gym. While the project faced several unforeseen challenges—as renovations often do—Jason was exceptional at stepping up. He rectified every situation with professionalism and integrity. A special shoutout to Trevor who was an excellent communicator throughout the process. He was punctual, kind and knowledgeable. We are very happy with the final result and highly recommend them for their craftsmanship and accountability.
We had an amazing experience working with Bonsai Builders for our kitchen remodel! From the very beginning, they made the entire process so easy and stress-free. I knew absolutely nothing about matching cabinets, flooring, countertops, and finishes, but their team guided me every step of the way and helped bring everything together beautifully.
What I appreciated most was how mindful they were of our budget while still helping us create a kitchen that looks high-end and cohesive. Their showroom was incredibly helpful because they had real samples and demos to see in person, which made choosing colors and materials so much easier and gave me confidence in my decisions.
The team was professional, patient, easy to work with, and truly cared about making sure we loved the final result. I would absolutely recommend them to anyone looking to remodel their kitchen!