Contractor review needed. This planning scenario is available only for a standard, conventional, single-story detached ADU of 400–800 sq ft in Miami-Dade without known exceptional site or structural conditions. Other projects need individual review.
This estimate is preliminary and not precise.It is not a quote or guarantee. Actual costs can fall outside this range and vary with the property, project scope, permits, site conditions, and contractor.
For a property-specific assessment and written quote, contact a contractor in the directory and verify their license.
View the contractor directory This is not an all-in ceiling or an official fee assessment. Land, financing and holding costs, tax and insurance changes, and unconfirmed survey, engineering, or exceptional work are excluded or need separate review.
Methodology and sources
The range is a regional reference, not Mount Olympus pricing. Size alone does not establish legal eligibility. A property review and contractor proposal are required.
Published construction: $200–$400 per sq ft. Bundled design + permitting: $8,000–$25,000. Bundled site work, utilities + potential impact fees: $10,000–$40,000+. These are contractor-published regional guide figures, not itemized bids or official fees.
The default 15% reserve is an editable planning assumption used by this tool, not a published source rate. It applies once to the subtotal. Only the final scenario is rounded outward to the nearest $5,000.
Source: Tella Builders · Published August 13, 2026; checked October 1, 2026.
Exact permit and impact fees depend on jurisdiction, classification, scope, credits, and agency assessment. Water and sewer connection charges are separate from impact fees. Confirm what each allowance covers.
Miami-Dade permit fee schedule · Miami-Dade impact fees