ADU Calculator

ADU Investment Calculator

Location-aware underwriting using 2026 Florida market tiers. Central Florida defaults to $1,600/mo — about $19,200 annual gross and an estimated $160,000 equity boost (monthly rent × 100).

Section 1 — Your Property and Build

Orlando, Winter Garden, Clermont, Kissimmee. ADU rent anchors to local 1-bedroom apartment averages plus a 10–15% privacy premium. Pick a specific area below for submarket detail.

Select a county to load jurisdiction-aware size caps in the calculator.

Slider follows ADU type limits; select a county for regulatory caps (1000 sq ft default guard until you do).

Includes design, permitting, construction, and inspection. Does not include land cost. Final cost confirmed after free site evaluation.

Section 2 — Financing

= $20,000

Loan amount: $80,000

Est. monthly loan payment: $644

Section 3 — Monthly expenses and assumptions

These are conservative estimates. Actual expenses vary. Review with a CPA before making financial decisions.

Estimated Monthly Rent

Conservative

$1,450

Market Rate

$1,600

Optimistic

$1,850

Based on Mid-metro / Central Florida market data for a 1-Bedroom ADU ($1,450 – $1,850/mo tier baseline).

Monthly Cash Flow

Gross rent$1,600
Vacancy (5.0%)- $80
Effective gross income$1,520
Insurance- $75
Maintenance reserve- $63
Property tax increase- $100
Management fee- $0
HOA- $0
Utilities- $0
Loan payment- $644
Total expenses- $882
Net monthly cash flow$638

Annual and Investment Returns

Annual gross income$19,200
Annual effective income$18,240
Annual net cash flow$7,650
Build cost$100,000
Cash invested$20,000
Cash-on-cash return38.3%
Cap rate15.4%
Estimated equity gain$160,000
Estimated new property value+$160,000
Simple payback period13.1 yrs

Equity framework: monthly rent × 100 ($1,600 × 100 = $160,000). Actual equity gain varies by appraisal and market conditions.

10-Year Investment Outlook

10-year cumulative net income: $89,645

Estimated equity gain: $160,000

Combined 10-year return: $249,645

Rent estimates based on current market data from Apartments.com, Zillow, Zumper, and RentCafe for Central Florida (Q1 2026). ADU rents may differ from apartment complex averages. Estimates are not guaranteed.

All figures produced by this calculator are illustrative estimates only and are not guaranteed. Rental income estimates are based on current Central Florida market data and may not reflect actual achievable rents for your specific property, unit, or market conditions. Expense assumptions are conservative estimates - actual costs vary. Equity gain projections are not guaranteed and depend on appraisal, market conditions, and property-specific factors. This calculator does not constitute financial, investment, tax, or legal advice. PreFabricated.co strongly recommends consulting a licensed CPA, financial advisor, and real estate attorney before making any investment decision.

Want numbers specific to your property?

The calculator gives you a market-rate estimate. A free site evaluation gives you actual zoning, buildable area, and a real cost range for your specific lot.