Beyond the unit price: budgeting your ADU project

The unavoidable costs every ADU project carries on top of the unit, whether you build with Nestron, another prefab, or on site. Nestron buyers typically land at ~$80K to ~$150K all in.

Beyond the unit price: budgeting your ADU project

A recent r/AccessoryDwellings thread, titled "Neighbor's cost of building an ADU in San Diego came in at $340K and the breakdown was eye opening," has been making the rounds. 180+ upvotes, 160+ comments, mostly from people sharing their own surprise totals.

We see the same surprise at Nestron. Prospects who get excited about a unit at $49,800 to $89,800 sometimes go quiet after a local contractor walks the lot and comes back with another $25K to $50K in site work, permits, and fees. The all-in number doesn't match the unit number, and it can feel like something was withheld.

Every legal ADU carries the same local costs on top of the unit, no matter who built it. What changes the headline total is the unit itself. A site-built or large-format prefab ADU drives totals like the $340K project above. A Nestron unit, fully built and finished in the factory, keeps the headline far lower.

Typical Nestron project, all in
  • Unit (factory-built and finished)$49,800 – $89,800
  • Shipping + delivery$15K – $25K
  • Local site work, utilities, permits, fees$15K – $40K
  • All-in total~$80K – $150K

This piece walks through two real Nestron projects (one harder lot, one simpler) and how to build a budget for your own.

Two real Nestron projects, end to end

The clearest way to show what an all-in number looks like is to walk through real examples. Both come from recent customers. Numbers anonymized and rounded.

High-end example: Pacific Northwest customer with above-average site challenges. Dead-end street that required road closure permits for craning, and existing utility lines about 8 feet deep that made the sewer tie-in more involved than usual.

High end · harder lot
Project total~$122,000
Nestron Cube Two (base unit, fully built)
$69,800
Shipping + port-to-site delivery
$20,000
Foundation (4 concrete pier footings)
$3,000
Water line tie-in
$1,500
Power conduit + tie-in
$3,000
Sewer line (8 ft deep)
$8,000
Craning with road closure permits
$10,000
System Development Charge (deferrable, ~$60/mo over 120 months)
$7,000

Low-end example: Florida customer on a straightforward site. Flat lot, utility mains close to the build, easy crane access, and a lower-fee jurisdiction typical of much of the Southeast.

Low end · simpler lot
Project total~$101,800
Nestron Cube Two (base unit, fully built)
$69,800
Shipping + port-to-site delivery
$20,000
Foundation
$3,000
Utility connections (water, sewer, power)
$2,000
Crane + installation
$5,000
Permits + impact fees
$2,000

Across our customer base, the local-cost portion of an ADU project typically falls $15K to $40K. Harder lots like the Pacific Northwest example run higher; simpler lots come in lower.

Soft costs (permits, design, engineering, plan check, financing) typically account for 10% to 25% of total project budget, per Terner Center for Housing Innovation at UC Berkeley.

Beyond the unit price: budgeting your ADU project
A Cube Two on the factory floor — fully built and finished before it ships. Everything you see is part of the unit price; everything that happens once it lands on your lot is local.

What's in your Nestron pricing, and what comes from local?

The advertised Nestron unit price covers what we build and what we directly control. Local-cost categories come from local contractors operating under local code.

In your Nestron pricing
  • The unit, fully built and furnished
  • Product design and architectural drawings
  • Jurisdictional permitting audit
  • Shipping coordination
  • Installation coordination with your local contractor
From local contractors
  • Permits, impact and connection fees
  • Foundation work
  • Utility trenching and tie-ins
  • Crane operation
  • General contractor coordination fees

We don't quote local costs because we can't quote them accurately. Permit fees, utility distances, and labor rates all vary by location. A vertically integrated builder will quote one all-in number, but that number typically carries a 20% to 30% markup on the local work to cover their risk. Most Nestron buyers come out ahead paying actual local cost with direct visibility into the bids.

Build your own budget

1
Unit + delivery

Unit prices: $49,800 (Cube One, Legend One), $69,800 (Cube Two, Legend Two), $89,800 (Cube Two X). Add shipping at $15K to $25K. Your project manager confirms a current shipping estimate close to your purchase date.

2
Site cost

Get a written estimate from a local GC, civil engineer, or permit expediter covering site prep, foundation, utility tie-ins, permit and impact fees, and any code-required additions. Typical lots land $15K to $40K.

3
Contingency

Add 15% on top of the combined total. Most buyers don't use most of it; it covers the rare surprise like unexpected soil conditions or an old septic that needs decommissioning.

Typical all-in by model, standard lot
Cube One / Legend One
254 sq ft
Unit price
$49,800
Typical all-in
~$80K – $120K
Cube Two / Legend Two
328 / 375 sq ft
Unit price
$69,800
Typical all-in
~$100K – $135K
Cube Two X
398 sq ft
Unit price
$89,800
Typical all-in
~$120K – $150K

What does the all-in number cost per month?

~$840
/ month
$120K all-in financed over 30 years at current home equity rates (~7.5%).
Why this monthly figure works
  • Nestron units are permitted as permanent homes, so financing rates track traditional home loans (well below tiny-home or RV rates).
  • Most buyers use the unit as a rental, family suite, or downsize. Rental income or alternative housing cost usually covers the monthly payment.
Common financing routes

Nestron partners with RenoFi for buyers who want a vetted option, and you're free to use your own bank or a mortgage broker who has financed ADU projects before.

Beyond the unit price: budgeting your ADU project
Inside a Cube Two X. The finished space, post-budget.

Bottom line

Nestron's expertise is building well-designed tiny homes at market-leading value and getting them to your lot ready to live in. Our mission is to make home ownership simpler and more accessible for more Americans, whether the unit becomes a first home, an in-law suite, or a rental investment to grow wealth.

Permitting requirements are complex and different in every US county. We'd love to be experts in every one, but we can't. We support your project as much as we can along the way. Local costs beyond the unit are unavoidable for any serious ADU project, whether you build with Nestron, choose a competitor, or go stick-built.

Those local costs typically add $15K to $40K, plus $15K to $25K for shipping. The Nestron unit price is what we control, and we hold it firm. Most customers land ~$80K to ~$150K all in.

Have a specific lot in mind? Your Nestron project manager can walk through your numbers with you. The full lineup is at nestron.house.
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