Type G-2 · 376 sqft studio · Caldwell, ID
The Osprey ADU in Caldwell
A Osprey studio ADU in Caldwell starts at $140k turnkey and estimates to $925–$1,100/mo in rent — about 6.5–9.6% gross yield on a $137k–$171k Standard build. Here's how the 376 sq ft Type G-2 plan fits Caldwell lots, what it costs, and how fast it permits.
- Footprint
- 376 sqft
- From (Essential)
- $140k
- Est. Caldwell rent
- $925–$1,100
- Gross yield
- 6.5–9.6%
Why the Osprey fits Caldwell lots
The Osprey is a 376 sq ft studio + garage — a single open dwelling on one pre-approved footprint. Whether it's the right plan for your Caldwell lot comes down to how it sits against the local lot pattern below.
Caldwell has three common lot patterns: (1) older 50-70' wide grid lots near downtown and the College of Idaho campus, often with alley access and existing accessory structures; (2) suburban 70-85' wide subdivision lots in the newer Linder Road and Ustick Road corridors; (3) rural-fringe lots on the city's southern and western edges with larger acreage and septic systems. The first cluster has the most garage-conversion candidates; the second cluster the most clean detached fits.
Detached vs. garage in Caldwell: Caldwell splits more evenly between detached and garage conversion than most Treasure Valley cities. The older grid neighborhoods near downtown and the College of Idaho have alley-loaded detached garages that convert well at lower per-unit cost. The suburban subdivision lots accommodate the Kingfisher and Waxwing detached without issue. Goldfinch is also a popular Caldwell pick for cap-rate plays — Canyon County's lower build cost stretches it well.
What does a Osprey cost to build in Caldwell?
The Osprey starts at $140k turnkey at Essential finish. Most Caldwell owners build at Standard finish — $137k–$171k. Caldwell has the metro's lowest entry cost — median home values run $330-380k versus Ada County's much higher base — so the same build returns the strongest cap rate in the valley.
| Finish Tier | Per sqft | 376 sqft in Caldwell |
|---|---|---|
| Essential | $340/sqft | $115k – $143k |
| Standard | $405/sqft | $137k – $171k |
| Premium | $480/sqft | $162k – $202k |
Methodology: per-sqft rates match our cost calculator (Essential $340, Standard $405, Premium $480) with a 0.9–1.12 range factor for lot conditions. Build cost is roughly uniform across the Treasure Valley; what changes city-to-city is land, fees, the size cap, and the rent ceiling. See the full Caldwell cost breakdown →
What rent and return does a Osprey earn in Caldwell?
A studio ADU like the Osprey estimates to $925–$1,100/month in Caldwell. Against a Standard-finish build of $137k–$171k, that's roughly 6.5–9.6% gross yield — about $12,150 a year in gross rent at the midpoint, before expenses and financing.
Monthly rent (est.)
$925–$1,100
studio · Caldwell
Annual gross (mid)
$12,150
12 × midpoint rent
Gross yield
6.5–9.6%
rent ÷ Standard build
Rent is scaled from Caldwell's sourced 1-bedroom median (Apartment List Caldwell, 2026) by unit size — a disclosed estimate, not a measured comp for this exact plan. Gross yield ignores vacancy, expenses, and debt service. This is information, not financial advice; validate with a local property manager before you build.
Permits and timeline for a Osprey in Caldwell
Caldwell is in Canyon County. Steady College of Idaho student-and-faculty demand underpins ADU rentals near campus year-round.
Caldwell allows ADUs in most residential zones under its city code, with Canyon County rules applying to parcels outside city limits. Rural Sunnyslope and ag-heritage lots have larger setbacks and acreage minimums but more flexibility on placement.
The Osprey is part of the City of Boise's pre-approved plan set, so it comes as a complete, already-engineered set of construction documents. That gives you a running start on review in Caldwell (Canyon County) — each city applies its own process, but a finished plan set clears review faster than a custom design.
The other 5 pre-approved plans in Caldwell
Each pre-approved plan carries its own cost, rent, and lot fit in Caldwell. Compare the full set for this city.
Type A · 280 sqft
Goldfinch in Caldwell
The smallest pre-approved Boise ADU plan — a 280 sq ft studio that fits the tightest lots and the cleanest budgets.
$115k · est. $925–$1,100/mo →
Type B · 396 sqft
Waxwing in Caldwell
A 396 sq ft studio with more breathing room — full living, kitchen, and bath in a thoughtfully laid-out single space.
$135k · est. $925–$1,100/mo →
Type C · 491 sqft
Kingfisher in Caldwell
Boise's pre-approved 491 sq ft one-bedroom — separate bedroom, full kitchen, full living room, ready to permit.
$170k · est. $1,100–$1,300/mo →
Type D · 695 sqft
Kestrel in Caldwell
The largest pre-approved Boise plan — a 695 sq ft two-bedroom that lives like a small house.
$245k · est. $1,400–$1,675/mo →
Type G-1 · 396 sqft
Sandpiper in Caldwell
A 396 sq ft studio paired with a single-car garage — pre-approved, dual-purpose, builds your storage and your rental in one footprint.
$145k · est. $925–$1,100/mo →
The Osprey in nearby Treasure Valley cities
Same plan, different local rent, cost, and zoning. See how the Osprey pencils out a short drive away.
Osprey in Caldwell — frequently asked
How much does a Osprey ADU cost in Caldwell?
The Osprey (376 sq ft, Type G-2) starts around $140k turnkey at Essential finish in Caldwell. Most Caldwell owners build at Standard finish — roughly $137k to $171k. Per-square-foot build cost is close to the Boise baseline; caldwell has the metro's lowest entry cost — median home values run $330-380k versus Ada County's much higher base — so the same build returns the strongest cap rate in the valley.
What can you rent a Osprey for in Caldwell?
A studio ADU like the Osprey in Caldwell estimates to about $925–$1,100 per month, scaled from Caldwell's sourced 1-bedroom rent (Apartment List Caldwell, 2026). On a Standard-finish build that's roughly 6.5–9.6% gross yield. These are estimates, not a rent guarantee — confirm with a local property manager.
How long does it take to permit a Osprey in Caldwell?
Caldwell is in Canyon County. Steady College of Idaho student-and-faculty demand underpins ADU rentals near campus year-round. The Osprey is a complete City of Boise pre-approved plan set, so you start with finished, already-engineered construction documents — that shortens review in every Treasure Valley city versus a custom design, even though each city applies its own process.
Does the Osprey fit Caldwell's ADU size limit?
Almost always. At 376 sq ft the Osprey is a compact footprint — Boise caps ADUs at 900 sq ft, and most Treasure Valley cities set their own limit (often a share of the primary home's floor area). The Osprey sits well under the typical cap, so in Caldwell size is rarely the constraint — lot dimensions, setbacks, and access usually decide placement. We confirm Caldwell's exact size rule for your parcel during the free lot check.
Caldwell, Idaho · Type G-2
Build the Osprey in Caldwell
Free 24-hour lot check covering plan fit, your Caldwell zoning, cost, and the rent it could carry. Or call (208) 297-2036.