How We Built Our ADU in California: The REAL Cost & Timeline

Wondering how much it REALLY costs to build a detached ADU in California? In this video, I break down every single dollar spent on our 1,200 sq. ft. project—no hidden fees, just real numbers. From the first meeting with the architect to the final certificate of occupancy, I’m walking you through our entire 21-month journey. We cover the construction process, the specific fees (permits, school district, planning), and the rental income we are now generating from the unit. Whether you are a homeowner looking to add space for family or an investor seeking passive income, this transparency will help you plan your budget. PROJECT SPECS: Location: Orange County, CA Unit Size: 1,200 Sq. Ft. (Detached) Layout: 3 Bed / 3 Bath Total Cost: ~$285,000 Cost Per Sq. Ft: ~$237.50 Current Rent: $4,200/month ⏱️ TIMESTAMPS 0:00 - Intro & Project Overview 0:26 - The Specs (1,200 Sq Ft Unit) 0:40 - The Full Timeline (21 Months) 1:02 - The Total Cost Reveal 1:43 - Rental Income & ROI ($50k/year) 1:55 - Architecture & Planning Phase 02:50 - The Hidden Fees (School & Public Works) 03:17 - Construction: Foundation & Site Prep 03:45 - Framing & MEP (Mechanical, Electrical, Plumbing) 04:32 - Finish Work & Landscaping 05:17 - Detailed Cost Breakdown (Itemized) 06:30 - Major Lessons Learned & Advice ABOUT THIS VIDEO: Many people click away when builders hide the numbers. That’s why I’m sharing everything. We financed almost the entire project and navigated city delays, material costs, and inspections to build a cash-flowing asset in our backyard. CONNECT WITH ME: Website: https://www.aduscale.com Instagram:   / aduscale   Disclaimer: These numbers are based on my personal experience building in California between 2021-2023. Construction costs vary by location and time. This video is for educational purposes and does not constitute financial or construction advice. Always consult with local professionals. #ADU #RealEstateInvesting #HomeConstruction #CaliforniaRealEstate #PassiveIncome #ADUCalifornia #CostBreakdown