Guide · Quotes

Reading and comparing Denver ADU quotes (2026)

LAST VERIFIED: SEPTEMBER 2026 · SOURCES: DENVER CPD FEE SCHEDULES, DENVER WATER, PUBLISHED DENVER BUILDER PRICING

Direct answer: Wildly different ADU quotes in Denver almost never mean one builder is overcharging; they mean the quotes cover different things. One is a unit or construction price, another is an all-in project price with permits, utilities, and the Denver Water System Development Charge; one assumes perfect soil, another carries an allowance for it. Before comparing numbers, force every quote onto the same eleven lines below. Quotes that can't be itemized that way aren't comparable, and usually aren't complete.

§1 · THE ELEVEN LINES

Itemize every quote to these lines before comparing

ADU QUOTE ANATOMY, DENVER 2026
Line	What to confirm	Commonly missing
1. Design and engineering	Architectural plans, structural engineering, survey	Survey; landmark-review drawings
2. Permits and city fees	Building permit, plan review, zoning	Often listed as "by owner"
3. Denver Water SDC + tap fees	System Development Charge (July 2026: $2,170 inside Denver) plus tap and meter	The single most-missed line
4. Utility service	Electrical service or sub-panel, gas if any, sewer and water lines to the unit	Trenching distance; Xcel coordination
5. Site work and foundation	Excavation, soil report, foundation type	Soil allowance; expansive-soil mitigation
6. Shell	Framing, roof, windows, exterior	Fire-rated assemblies near property lines
7. Mechanical, electrical, plumbing	Heating/cooling system type, fixtures count	Heat pump vs. gas; ERV
8. Interior finish	Kitchen, bath, flooring, finish level with allowances stated	Allowance amounts left blank
9. Site restoration	Landscaping, fencing, driveway or alley repair	Almost always excluded
10. Contingency	Stated percentage, who controls it	Zero contingency is a warning, not a bargain
11. Exclusions	An explicit list of what the price does not cover	If there's no exclusions section, everything not listed is excluded

§2 · READING THE GAP

Why one quote is $160K and another is $280K for the "same" ADU

Run the two quotes through the eleven lines and the gap usually resolves into four causes: scope (lines 2, 3, 4, and 9 are missing from the lower one), method (a modular unit price vs. a site-built project price; see prefab vs. site-built), risk (one builder priced a soil allowance and a contingency, the other will invoice them as change orders), and finish (allowances of $40 vs. $120 per square foot for tile look identical on a summary page). Whatever's left after those four is the actual price difference, and it's usually far smaller than the headline suggested.

Two practical rules: ask each builder to re-submit on your eleven-line template (a serious builder will; the template protects them too), and never let a quote expire in under a week. See the full cost ranges in what an ADU really costs and how to check the builder behind the number in verify a contractor.

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