Cost-Effective ADU Builders in Hillsborough
Find contractors in Hillsborough that fit your budget. Projected income: $3,698/mo. Compare estimates and maximize your property value.
12
Contractors
$4K
Average Rent /mo
$4.9M
Avg Home Value
Companies & Contractors serving close to Hillsborough
Top-rated professionals serving Hillsborough and neighboring areas in San Mateo County
ADU Expansion Builders
Alliance Room Addition & ADU Contractors
Top Investment Neighborhoods
Highest rental yields in Hillsborough by ZIP Code
ZIP 94010
Highest Return
Top ZIP Codes by Rent in Hillsborough
Neighborhoods with the highest average rental rates
94010
Hillsborough Real Estate Market
Easy to understand market data to help you make informed ADU investment decisions.
Based on aggregated market data from multiple housing platforms and public records
Average Rent
Monthly rental price
$4K
Average Home Value
Property valuation
$4.9M
Market Analysis
Hillsborough shows strong rent growth of 5.9% over the past 12 months. Home values have increased by 5.3%, making ADU investment a strategic choice for homeowners.
Projected Property Value
Current market analysis for Hillsborough indicates a -0.7% increase in property values over the next 12 months.
Similar Cities to Hillsborough
Cities with similar market characteristics for comparison
California State ADU Standards
These are the guaranteed rights for homeowners in Hillsborough under California State Law. Local agencies cannot enforce stricter standards than these baselines.
State law prohibits local agencies from setting limits below 850 sq. ft. (1 bd) or 1,000 sq. ft. (2 bd). Generally, up to 1,200 sq. ft. is allowed subject to setbacks.
Local agencies cannot require rear or side setbacks of more than 4 feet.
Minimum allowed height limit. Some areas allow up to 18-25ft depending on proximity to transit or main house.
No parking required if ADU is within 1/2 mile of public transit, historic district, or part of existing home footprint.
State law currently prohibits owner-occupancy requirements for ADUs permitted between 2020 and 2025.
Development impact fees are waived for ADUs smaller than 750 sq. ft. For larger units, fees must be proportional.
* While these state laws provide a baseline, always verify specific local overlay zones or fire safety regulations with the Hillsborough planning department.
Building ADUs in Hillsborough
Building an Accessory Dwelling Unit in Hillsborough is a significant investment, but finding the right partner can keep costs manageable. Our list includes 12 builders serving San Mateo County.
In the current Hillsborough real estate market, adding square footage is one of the best ways to force appreciation. Plus, with rental potential of $3,698/mo, the unit can often pay for itself over time.
Frequently Asked Questions about ADUs in Hillsborough
Common questions from local homeowners
ADU construction costs in Hillsborough typically range from $250-$400 per square foot for standard construction. For a 500 sq ft unit, this translates to $125,000-$200,000. Garage conversions are usually more affordable, often costing 30-50% less than new detached construction.
ROI Intelligence
Investment insights for Hillsborough
Market Rent
$4K/mo
Est. Annual Income
$42K
Est. ROI
19.0%
Monthly Cash
$3K
Value Growth (12m)
+5.3%
*Estimates based on average ADU size (800 sqft) and construction costs ($200K). Actual results may vary. Use calculator for personalized analysis.