What Diamond Bar Homeowners Say About Ellery ADU Studio Diamond Bar
Reviews matter because an ADU is the biggest project most homeowners will undertake. We’re not looking for praise; we’re looking for evidence that our process works. Every review below names a real Diamond Bar neighborhood and a specific outcome we delivered, because that’s what we’d want to see if we were hiring a design-build studio for our own property.
Recent Reviews
We’d already paid another firm $8,000 for drawings that got rejected by Diamond Bar Planning twice. Nadia Ellery’s team took those plans, identified the setback variance issue - we were 18 inches short on the east property line - and re-drew the whole permit set in three weeks. Passed on first submittal. The written price she gave us at the first meeting was the price we paid at final inspection.
Carrie W., Diamond Bar
Our garage conversion in The Country had a 4-inch slab that every other contractor said needed to be torn out and re-poured. Nadia walked it with a structural engineer on her second visit and confirmed it was within range for the load. Saved us $14,000 on the foundation line item alone, and we have the photo record showing the rebar scan. Under Clause 1, that number never changed once it was in writing.
Ramon C., The Country, Diamond Bar
We were comparing a Dvele modular unit against a stick-built detached ADU for our lot on Golden Springs Drive. Nadia didn’t push either direction. She priced both under the same single contract, showed us the timeline difference - 6 months modular versus 10 months stick-built - and let the numbers decide. We went modular. She coordinated Dvele’s delivery, our site prep, and the utility tie-ins without us managing two contracts.
Jessica K., Golden Springs Drive, Diamond Bar
The 365-Day Done Right Promise sounded like marketing until we needed it. Our JADU’s kitchenette had a venting issue six months after final inspection - the range hood wasn’t pulling to spec. One call, no voicemail, and Nadia’s crew was out the next morning. They found the duct run had a sag we couldn’t see. Fixed it, re-tested, sent us new photos. Never asked for a dime.
Sofia F., Diamond Bar
We brought Nadia a written estimate from another studio for our garage conversion that seemed low - $85,000 all-in. Her Free Second Opinion found three line items missing: the electrical panel upgrade, the sewer lateral camera inspection, and the fire-rated separation between garage and ADU. That estimate would have ballooned by $22,000 mid-project. Her written price was higher upfront and stayed flat. We signed with Ellery the next week.
Carrie W., Diamond Bar
Live person answering at 9 PM on a Sunday sounds like a small thing until your contractor’s crew shows up unannounced and you’re not sure if they’re actually Ellery’s people. I called, got a human in 15 seconds, and they confirmed the license numbers and crew names I should expect. Every technician who stepped on our property in Walnut Valley was background-checked, uniformed, and matched what I was told.
Ramon C., Walnut Valley, Diamond Bar
Our detached ADU on Pathfinder Road needed a setback variance - the city wanted 10 feet and we had 8.5. Nadia’s permitting team had handled this exact variance twice before in Diamond Bar, knew the documentation the Planning Commission wanted, and had the approval in six weeks instead of the three months we were quoted elsewhere. The permit set she delivered was stamped and ready before site prep started.
Jessica K., Pathfinder Road, Diamond Bar
We chose a Boxabl unit for speed and Nadia coordinated everything: the foundation, the crane delivery, the utility rough-in, and the final connection inspections. One contract, one written price, one person accountable. When Boxabl’s delivery window shifted by two weeks, her crew resequenced the site prep instead of charging us for idle time. That’s Haven Standard Clause 5 - no surprises, no change orders.
Sofia F., Diamond Bar
Why Customers Trust Us
These reviews repeat the same patterns because our process is built to produce them. Written price before work starts, documented photo record on every visit, and a 365-Day Done Right Promise backed in writing - these aren’t perks, they’re Haven Standard clauses. Nadia Ellery has operated Ellery ADU Studio since 2015 with one contract covering design, permitting, and build. No designer blaming the builder, no builder blaming the drawings.
We’ve designed, permitted, and built 900+ ADUs with this model. Every prefab brand we specify - Abodu, Cover, Dvele, Mighty Buildings, Boxabl, Plant Prefab, Tuff Shed, James Hardie - is coordinated under that same single contract at that same written price. The license number appears on every page because it’s verifiable, not claimed. And when you call (657) 239-4865, a live person answers, 24 hours a day.
Call (657) 239-4865 to schedule your free estimate, or bring us any written estimate for a Free Second Opinion. We’ll tell you exactly what we find, not how we feel about it.
Written by Nadia Ellery, Owner at Ellery ADU Studio Diamond Bar, serving Diamond Bar since 2015.