1184 Dorset Lane, Costa Mesa: A Reimagined Single-Story with a Brand-New 2-Bed ADU and $2,800/Month Built In
This property just went Coming Soon. Here's what you need to know before the open house.
1184 Dorset Lane, Costa Mesa 92626
List price: $1,749,000
3 bed / 2 bath main house + 2 bed / 1 bath ADU
2,055 sq ft total | 6,500 sq ft corner lot
ADU: 655 sq ft | Built 2025 | Fully permitted | Separate entrance | Separate electric meter
Estimated rent: $2,800/month
A fully permitted, brand-new 2-bedroom ADU in Costa Mesa is a rare find at any price. On a corner lot in one of the city's most walkable neighborhoods, with the main house freshly renovated and owned solar already paid off, this one has a lot going for it at once.
The Main House
The original structure is a single-story California ranch from 1960, fully reimagined on the inside. The main house runs 3 bedrooms and 2 bathrooms, and the renovation didn't leave much untouched — wide-plank vinyl flooring throughout, recessed lighting, and a wide-open great room where the kitchen, dining, and living areas flow together without walls in the way.
The kitchen is the anchor: a quartz island with seating for four, shaker cabinetry, and stainless appliances including a gas range, microwave, dishwasher, and refrigerator. Both bathrooms were redone. There's a gas fireplace in the living room, central A/C and heat, and in-unit laundry (washer and dryer included). The exterior got fresh paint and low-maintenance turf landscaping, and there's a covered patio in the back.
The owned solar panels — already paid off, not leased — are built into the deal. No monthly solar payment eating into your cash flow from day one.
The ADU: 2 Bed / 1 Bath, $2,800/Month
The ADU was built in 2025 and is fully permitted through the City of Costa Mesa. At 655 square feet, it's a genuine two-bedroom unit — not a studio dressed up as a guest suite. It has its own separate entrance, its own kitchen (range, refrigerator, sink, stove), and its own electric meter, which is the configuration that matters most for how lenders treat the income at underwriting.
Under California's state ADU law, a separately metered, permitted ADU like this one can have its projected rental income counted by a lender when you're qualifying for a purchase loan. That means the $2,800/month can offset your mortgage qualification — which changes the real net cost of carrying a $1,749,000 property in a meaningful way.
At $2,800/month, that's $33,600/year in gross ADU income. The separate electric meter means utilities are the tenant's responsibility. Add in what the paid-off solar does to the main house's operating costs, and the monthly picture looks different than the sticker price suggests.
The Investment Case
Costa Mesa is not a market where 2-bedroom ADUs show up often in the MLS. The City of Costa Mesa's ADU program allows them, but between lot coverage limits, setback requirements, and the cost of new construction, most of what trades in this city is a garage conversion or a JADU — not a full two-bedroom unit with its own entrance and separate utilities. This one was built new in 2025 and fully permitted. That matters at appraisal and it matters at underwriting.
How a home with an ADU is valued when you sell in Orange County depends heavily on permit status and utility configuration — a permitted, separately metered ADU is worth more to a buyer's lender than an unpermitted unit that generates income but can't be formally counted. Fannie Mae's updated ADU income guidelines allow lenders to use projected market rent from a new ADU even before it's occupied, which is relevant here since the unit is currently vacant and not yet rented.
For an investor buyer, the numbers look like this: $1,749,000 purchase price, $2,800/month ADU income, and the option to rent the main house as well — or to occupy it while the ADU offsets the mortgage. The three benefits that stack behind every SoCal income property — cash flow, appreciation, and depreciation — all run simultaneously here. Costa Mesa appreciation is not speculative. It's durable, and this is a corner lot on a 6,500 sq ft parcel in a walkable pocket of the city.
For an owner-occupant, this is a house-hack setup that actually works. Live in the 3-bed main house, rent the ADU at $2,800/month, let the income reduce your effective mortgage payment. Before you write an offer on any property with an existing ADU, there are a few permit, utility, and financing questions worth running through — especially when ADU income will factor into your loan qualification. This property checks those boxes cleanly, but it's still worth knowing what to verify before you're in escrow.
Location
Mesa North is one of the more walkable pockets in Costa Mesa's 92626. The Westside Costa Mesa restaurant scene is minutes away. South Coast Plaza is close. The coast is a short drive. Newport Mesa Unified runs the schools. No HOA. No Mello-Roos. No shared walls between the main house and the ADU. Just a turnkey single-story on a corner lot with a brand-new income unit attached.
For market context, ADU-equipped properties in nearby Garden Grove and Anaheim have been moving decisively when the income story is clean and the permit status is clear. Costa Mesa carries a meaningful premium over those markets on a per-square-foot basis — which is exactly why a 2-bed permitted ADU at $2,800/month moves the math here in a way it wouldn't in every zip code.
Quick Look
Main HouseADUBedrooms32Bathrooms21Sq Ft~1,400 (approx.)655EntranceFrontSeparateUtilitiesOwned solarSeparate electric meterStatusVacantNot currently rented
List Price: $1,749,000 ADU Asking Rent: $2,800/month Open House: Sat July 26, 10am–1pm | Broker Preview Fri July 25, 11am–2pm
Interested in This Property?
Schedule a showing with Dylan Serna at (714) 860-2868
Dylan Serna | ADU Specialist | DRE 02217359 | adurealtor.net
