Licensed CA General Contractor · Veteran-Owned

Home Addition & ADU Cost Calculator for Southeast LA

Ballpark your project in 30 seconds. No login. No email. Just numbers from a licensed builder.

📞 (213) 578-5303, call or text

Serving homeowners in Downey, Lakewood, Whittier, Pico Rivera, Cerritos, Norwalk, and across Southeast LA.

CA LIC #1142540
Licensed General B
VETERAN OWNED
Family Operated
CERTIFIED
50+ Years Experience
SERVICE AREA
Downey, Lakewood, Whittier & SE LA

Budget Tool

Project Budget Calculator

Select your project type, size, and finish level to see your estimated range.

Step 1 of 3, Project Type
01 · Project Type

Estimated Budget Range

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This is a planning-level estimate based on regional averages. Your actual number depends on your site, scope, permitting, and material selections.

These ranges are based on 2026 Southeast LA market data. Because every home is unique, your final number will depend on your specific site and material selections. As an owner-led, father-and-son team, we manage your build directly. This keeps our process highly efficient, ensuring your budget goes exactly where it belongs, toward high-quality, fully licensed craftsmanship. Get a real number, book a free 15-min call with Jose.

Next Step

Want to Turn This Into a Real Number?

This is a planning-level estimate. Share a few details and we'll follow up with next steps.

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Phone
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City
Timeline
Notes (optional)
CA Lic #1142540 50+ Years Experience Serving Southeast LA
or
(213) 578-5303

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We'll review your project details and get back to you within one business day.

What Clients Say

Recent Project Reviews

★★★★★

"Reystone Construction did an outstanding job converting our garage into a fully permitted 2-bedroom, 2-bathroom ADU. From the initial consultation to the final walkthrough, the entire process was smooth and professional. Jose and his team were communicative, detail-oriented, and committed to quality at every stage."

Gabriel G. · South Gate Garage → 2BR/2BA ADU
★★★★★

"From consultation to the final walkthrough, the team stayed on schedule and within budget. Communication was clear throughout, and the craftsmanship exceeded expectations. Highly recommend for anyone looking for reliable, high-quality construction work."

Miguel R. On Schedule & On Budget
★★★★★

"Had a great experience with Reystone Construction on a bathroom refresh. The team was professional, on time, and the attention to detail really stood out. Everything was done right the first time. Would definitely hire again."

Anthony M. Bathroom Refresh

Google Reviews · 5.0 ★★★★★

Crew framing the garage opening for ADU conversion
ADU interior with drywall mudded, taped, and recessed lights installed
Bathroom tile installation in garage-to-ADU conversion
ADU exterior with new window and door cutouts during lath prep

Current Project

683 SF Garage Conversion , Los Angeles County

Full conversion from garage to permitted living space. Framing, electrical, plumbing, HVAC, drywall, and finish, documented from day one.

Rough inspections passed. Final inspection pending.

What to Expect

From Calculator to Contract

01
Run Your Numbers
Use the calculator above for a ballpark range
02
Share Your Project
Submit the form or call us directly
03
Site Visit & Scope
We walk the site and define the real scope together
04
Written Quote
Line-item estimate within 3–5 business days

No deposit required until you approve the scope and sign.

Ready to talk?

Get a Real Quote

Tell us what you're looking to build. We'll get back to you within one business day.

(213) 578-5303

📞 (213) 578-5303 Get Estimate