Published, dated market reference. Your assessment numbers above are yours to change.
| Build type | $ / sqft | Typical | Source · as of |
|---|
| Size | All-in range | Note |
|---|
| Item | Share | $ range |
|---|
Net rental income (before operating costs) = gross rent × (1 −
vacancy). Any operating costs you enter (insurance, maintenance & reserves, management, owner-paid utilities) come off next.
Breakeven (years) = simple undiscounted payback: accumulate
net rental income after any operating costs you entered (rent compounding at the growth rate) until it repays the total
project cost. Cap 40 years.
Loan payment = standard amortization P·r ⁄ (1
− (1+r)⁻ⁿ); a HELOC is interest-only during
its 10-yr draw, then amortizes.
Property tax = tax(home + ADU value) − tax(home), where tax(V) = V × 7.05% × school mills ÷ 1000 + (V − 10% of the first $700,000 of V) × 6.80%
× local-government mills ÷ 1000 — TY2026 assessment rates × TY2025 levies (payable 2026), a mixed-year estimate
until TY2026 levies are certified. The ADU value is an assumption (build cost × a per-area factor).
Wealth = value created day one (added market value −
project cost) + appreciation on that added value + loan principal
paid + cumulative cash flow, over your hold.
Total project cost = Olerra’s turnkey price = the factory-built unit (Olerra’s unit-only price) + site work, foundation, utility connections, delivery & set, design, permits & fees. City fees are inside the second part and listed once — never added on top.
No. Colorado assessors add only what the ADU contributes to your property's market value — in strong markets like Boulder often more than the build cost† — on top of your existing valuation. The new value first appears the January after the ADU is finished, and you start paying on it the following year.
Not exactly. HUD's FY2026 Fair Market Rents are 40th-percentile recent-mover rents used for voucher programs — a solid, conservative baseline. A brand-new, well-finished ADU often rents above FMR. We default to a conservative baseline — HUD FMR in most areas (a labelled regional estimate where no single HUD area fits) — and let you edit the rent to your local numbers.
The 2024 state ADU law requires many Front Range municipalities to allow at least one ADU on single-family lots and limits the most restrictive local barriers, like blanket owner-occupancy mandates. Cities still set their own size caps, fees and design rules — which is why Boulder, Denver and Fort Collins look so different in this tool.
Boulder requires fire sprinklers on detached ADUs, which adds roughly $3–10K to construction, and its plant-investment fees are among the highest in the metro. The upside: sharing your main house's existing water and sewer service avoids about $12,700 of those fees, which otherwise sit inside Olerra’s turnkey price — your quote reflects your actual fees. See the toggle in section 1.
If your lot is served by City utilities, an ADU sharing the main meter pays water and wastewater charges by a published method (January 2026 rates); the City’s worked examples run $1,984.00–$14,949.12, and those charges sit inside Olerra’s turnkey price. But if you're in a special district like Fort Collins–Loveland Water District (FCLWD), a new water tap was $55,685 on the January 2026 schedule — an outlier that can push a project toward or above the top of Olerra’s turnkey range. Confirm your water district before you budget anything.
No. This is a pre-tax planning estimate to help you think through the decision. It is not a quote, an appraisal, or financial advice, and Olerra is not a lender or financial advisor. Confirm fees, rates and tax treatment with your city, lender and a tax professional before committing.
In production this opens Olerra's scheduling flow — an Olerra advisor walks your property, confirms fees with your city and water district, and quotes a fixed price on a 490 or 735. For this prototype it's a stub; no data is sent.
