Which is bigger, the Six Sixty or the Twelve Hundred?

The Twelve Hundred is bigger at 1,200 sq ft, compared to 660 sq ft for the Six Sixty.

Which costs less, the Six Sixty or the Twelve Hundred?

The Six Sixty is the lower-priced option at $309,000, which includes a permitting budget along with plans, foundation, and delivery, compared to $549,000 for the Twelve Hundred. Exact permit costs are set by your city or county and confirmed in your feasibility study.

Which one delivers faster, the Six Sixty or the Twelve Hundred?

The Six Sixty has the shorter typical timeline at 5 months, compared to 7–9 months for the Twelve Hundred.

When should I choose the Six Sixty over the Twelve Hundred?

Choose the Six Sixty if you want the most efficient path to rental income or a comfortable, private space for parents or adult children without a long wait.

When should I choose the Twelve Hundred over the Six Sixty?

Choose the Twelve Hundred if you want a full size home with room for a growing family, built to serve as a real primary residence.

Six Sixty vs Twelve Hundred

The Six Sixty and the Twelve Hundred sit at opposite ends of what an ADU can do for you. The Six Sixty is a 660 square foot, one bedroom, one bathroom home priced at $309,000 with a build timeline of about 5 months. The Twelve Hundred is a full 1,200 square foot, three bedroom, two bathroom home priced at $549,000, with a build timeline of 7 to 9 months.

At a Glance

	Six Sixty	Twelve Hundred
Size	660 sq ft	1,200 sq ft
Bed / Bath	1 Bed / 1 Bath	3 Bed / 2 Bath
All-Inclusive Price*	$309,000	$549,000
Typical Delivery	5 months	7–9 months
Footprint Shape	Rectangular	L-shaped
Best For	Rental income, parents, adult children: the all-rounder.	Primary residences, large families, maximum resale value.

*Includes a permitting budget, not final permit costs. Permits and property-specific site work (septic, retaining walls, etc.) vary by property and are confirmed in your feasibility study. Every price also includes plans, foundation, the factory build, delivery, utility hookups, appliances, and final inspection.

Where the Six Sixty Wins

Pick the Six Sixty for this.

● Most popular model, the proven all-rounder
● Lower price point at $309,000, 5 month build
● Built for rentals, parents, or adult children

Where the Twelve Hundred Wins

Pick the Twelve Hundred for this.

● 1,200 square feet, room to spread out
● 3 bedrooms and 2 baths for a full household
● L-shaped layout built for resale value

The Honest Verdict

How to actually decide.

If your priority is rental income or a quick, efficient space for one or two people, the Six Sixty is the smarter build. If you need enough room for a whole family to actually live in, the Twelve Hundred is the one that gets you there.

Choose the Six Sixty if: Choose the Six Sixty if you want the most efficient path to rental income or a comfortable, private space for parents or adult children without a long wait.
Choose the Twelve Hundred if: Choose the Twelve Hundred if you want a full size home with room for a growing family, built to serve as a real primary residence.

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Still Deciding?

See which one actually fits your lot: the Six Sixty or the Twelve Hundred.

Every property is different. Tell us your lot size, budget, and what you need the space for, and a real person on our team will tell you which model works, plus your exact price with permitting and site work factored in.

A shortlist of which models actually fit your lot
Honest flags on anything property-specific, like slope or septic
A clear next step, whether that is a factory tour or a feasibility study
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Once you submit, a real person on our team reviews your property and follows up within 1 to 2 business days to book your free 30-minute call. No call center, no drip campaign, just a conversation.

After we review your property, we'll invite you out to the factory, or send a member of our team to you, whichever fits your schedule better.

Building more than one? If you're a real estate developer or investor planning multiple units, let us know in the form. We offer better pricing at volume.

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