Best ADU For · 2026
Best ADU for First-Time Investors: Which Model Wins
If you are building your first rental ADU and want the strongest return for the least risk, the Six Sixty 2BR is the model to build. It runs $309,000 with a permitting budget already built in, delivers two bedrooms and one bath in 660 sq ft, and rents like a two-bedroom while costing barely more than a one-bedroom in the same footprint. For a first-time investor, that rent-to-cost ratio is hard to beat anywhere in our lineup.
The short version: The Six Sixty 2BR wins for first-time investors because it packs two bedrooms into a compact, affordable 660 sq ft footprint at $309,000, so you collect two-bedroom rent without paying two-bedroom construction costs. The one-bedroom Six Sixty ($287,000) is the safer, lower-entry alternative if you want to keep the initial check smaller, and the Five Five Five ($267,000) is the lowest-cost path to a rentable one-bedroom if budget is the deciding factor.
Why first-time investors need a different kind of ADU
A first rental ADU is not the place to experiment with a large, ambitious floor plan. You are learning how to be a landlord, testing your local rental market, and, in most cases, working with a fixed construction budget you cannot easily expand mid-project. The model you pick has to do three things at once: keep the upfront cost manageable, produce rent that clearly justifies the build, and lease quickly once it is done.
That combination rules out both ends of our lineup. The smallest studio models keep costs low but cap your rent at studio rates, which stretches your break-even timeline. The largest three-bedroom homes rent for more, but they also carry the highest price tags and the longest build timelines, which is more capital risk than most first-time investors want to take on before they have proven the model works for them.
The sweet spot for a first rental is a compact, efficient floor plan with enough bedrooms to command real rent, built at a price where the monthly payment pencils out against realistic local rents. That is exactly the gap our 660 sq ft models fill, and it is why they are the ones we point first-time investors toward.
The models that fit
These three models cover the range a first-time investor should actually consider, from the lowest entry cost to the strongest rent-to-cost ratio.
| Model | Size | Beds/Baths | All-inclusive price* | Why it fits |
|---|---|---|---|---|
| Five Five Five | 555 sq ft | 1 / 1 | $267,000 | Lowest-cost path to a real, rentable one-bedroom |
| Six Sixty | 660 sq ft | 1 / 1 | $287,000 | Our most popular model, easy to rent almost anywhere |
| Six Sixty 2BR | 660 sq ft | 2 / 1 | $309,000 | Two bedrooms in a one-bedroom footprint, top pick for rentals |
*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.
The winner: Six Sixty 2BR
The Six Sixty 2BR earns the top spot because of one simple fact: it fits two full bedrooms and a bathroom into the same 660 sq ft footprint as our standard one-bedroom Six Sixty. You pay $309,000, just $22,000 more than the one-bedroom version, but you unlock a second bedroom that opens the door to renting by the room, housing a small family, or splitting the unit between two roommates paying separately. In most local rental markets, a second bedroom adds meaningfully more in monthly rent than a $22,000 price gap costs you in financing.
That is the whole case for a first-time investor: you are not paying for square footage you do not need, you are paying for the one feature (a second bedroom) that moves the needle most on what a tenant will pay. The build timeline is 5 months, which is fast enough that you are not carrying a construction loan and an empty lot for the better part of a year before you see your first rent check. The rectangle layout keeps the build simple and the factory process efficient, which is part of why this model, along with the standard Six Sixty, is one of the fastest-delivered homes in our lineup.
The runner-up: Six Sixty
If your budget is tighter or you would rather keep the entry check as small as possible while you learn the ropes of being a landlord, the standard Six Sixty is the safer starting point. At $287,000, it is our single most popular model across all buyers, not just investors, which tells you something: a one-bedroom, one-bath 660 sq ft unit is an easy, dependable rent almost anywhere in California. It works for a single tenant, a young couple, an adult child, or an aging parent, which means if your rental plans ever change, the unit adapts with you.
The tradeoff versus the 2BR version is straightforward. You save $22,000 upfront, but you give up the ability to rent by the room or command the higher rent a second bedroom typically brings. For a first-time investor who wants the lowest possible barrier to entry and the broadest possible tenant pool, that tradeoff can make sense. For most investors focused purely on return, the 2BR still wins on rent-to-cost math. And if the budget needs to come down further still, the Five Five Five at $267,000 gets you a smaller but still fully rentable one-bedroom, one-bath unit, the lowest-cost way into the rental game in our entire catalog.
Pricing, financing, and next steps
Before you commit to a model, run your actual numbers. Our ADU income calculator lets you plug in local rent estimates against each model’s price, permitting budget included, so you can see the real return before you sign anything. If you are not yet sure what your specific lot allows, a feasibility study confirms buildability up front. And for a full breakdown of what is included in every price across all 14 models, see our pricing page.
For a broader look at the numbers behind an ADU as a rental investment, including the appraisal picture, see how much rent an ADU can earn in California and ADU appraisal and resale value.
Frequently asked questions
What is the single best ADU model for a first-time investor?
The Six Sixty 2BR. At $309,000 for 660 sq ft with two bedrooms and one bath, it delivers the strongest rent-to-cost ratio in our lineup because you get a second bedroom’s worth of rent for a small increase over the one-bedroom price.
Is a smaller, cheaper model a better first investment?
Not usually, if your goal is return on rent. The Five Five Five at $267,000 lowers your upfront cost, but a 555 sq ft one-bedroom rents for less than a 660 sq ft two-bedroom, so the gap in rent often outweighs the gap in price over time. It is the right pick if minimizing the initial outlay matters more to you than maximizing monthly return.
How long does it take to build the Six Sixty 2BR?
About 5 months from contract to move-in ready, the same timeline as the standard one-bedroom Six Sixty. That is one of the faster build times in our 14-model lineup, which matters for an investor who wants to start collecting rent sooner rather than later.
Does a two-bedroom ADU really rent for more than a one-bedroom in the same footprint?
In most California rental markets, yes. A second bedroom typically lets you rent by the room, house a small family, or split rent between two tenants, all of which push monthly income above what a comparable one-bedroom unit earns, even when the square footage is identical.
Do I need to know my exact rent numbers before choosing a model?
No, but it helps. Start with the ADU income calculator to estimate rent for your area against each model’s price, then confirm what your specific lot can support with a feasibility study before finalizing your model choice.
Ready to see what your lot supports? Start with a feasibility study or browse the full model catalog to compare every layout side by side.