Home Improvements

Extend your home with ADUs or give it a stylish refresh with quality home improvements anywhere in Downey, San Marino, and more of South CA!

Scroll down to discover options, pricing, and process

Remain Comfortable In A home Built Exclusively for you

If you’re not 100% satisfied with your home’s looks, a complete interior or exterior remodel will fix everything.

And if everything about your home is perfect, all that’s left to do is expand.

Best part about that? You can make some passive income with a small rental property you can manage on your own property.

If you want a quality home improvement here in South CA without too much hassle and stress, we’ve got you covered!

Some fixes and updates you can get are:

Here's The Level of Craftsmanship You Can Expect

Frequently Asked Questions

A home improvement project includes a very wide range of projects, from replacing a leaky faucet to a complete home interior remodel. 

Here at Cornejo’s Builders, our focus is mainly on bigger home improvement projects, like remodels and ADUs. 

Because of that, we can tackle any kind of work, including installing new plumbing and electrical systems, deck and porch building, siding installation, window and door replacement, painting, and much more!

Complete home remodels are by far the most popular home improvement project homeowners start here in Downey, San Marino, and more of South CA.

These include complete demolition of existing interior home, and building new additions and remodeling bathrooms and the kitchen. 

The cost of a home improvement project is based on what kind of work you need to be done on your property. Because home improvements include a wide range of projects, prices can start from as low as $5k for a deck repair to over $200k for a complete interior remodel.

Most of our projects vary from 1 month to 4 months, depending on the scope of work, so they’re on the more expensive side of upgrades.

We charge based on the project’s scope of work, and then, based off of that, we’ll calculate the materials cost and add in the labor cost.

We can get you the highest-quality craftsmanship at a fair and reasonable price.

The home improvement process generally follows this workflow:

  • Assessment and planning: This stage involves identifying the areas of the home that require improvement, setting clear goals for the project, and creating a detailed plan for the work to be done.
  • Budgeting and sourcing materials: Establishing a budget for the project and researching the necessary materials, fixtures, and appliances.
  • Permits and approvals: Ensuring that any necessary permits and approvals are obtained before the work begins.
  • Demolition and preparation: Clearing out the space and preparing it for removing old fixtures, flooring, or cabinetry.
  • Renovation and construction: Carrying out the actual improvement work, such as installing new flooring, updating electrical or plumbing systems, and making structural changes if necessary.
  • Installation of new components: Adding new fixtures, appliances, cabinetry, or other elements as required by the project plan.
  • Finishing touches: Adding final details such as paint, trim work, and making structural changes if necessary.

Yes! Cornejo’s Builders Inc offers a workmanship warranty for anything we’ve worked on. You’ll also enjoy the materials warranty which can range from a couple of years to over 50. 

Please note that the workmanship warranty is limited to exclusively what we’ve installed, and the materials warranty apply only for the materials we buy and install.

Home Improvement Cost And Upgrades

Check out some of our finished home improvement projects in South CA, what went into them, and what their total cost was.

Home improvement project

1,923 sq. ft. Interior Home Remodel in Hollywood, CA

The project included:
This home improvement project was quoted for $255,000, where the Milgard doors were $25,000 in total.

1125 sq. ft. Home Remodel in Downey, CA

This project included:

This home improvement project was quoted for $195,000, and the most expensive items were the custom kitchen cabinets at $10,000.

600 sq. ft. New Duplex Unit in Whittier, CA

This project included:

This project was quoted at $167,000, where the most expensive item was the tile for the walk-in shower, at $5,600.

An Dialed-In Home Improvement Process

Experience the true joy of upgrading your home without having to worry about anything. Sit back, relax, and enjoy watching your dream home come true with this 3-step process.



Contact us, and let’s plan your home improvement together.



Remain comfortable and on top of everything at all times.



Call your friends over and celebrate your new home upgrade!

A Local Expert Committed To You And Your Investment

Enjoy a complete home improvement service with an expert who takes care of everything for you. The biggest names in the industry back us up.

CW-logo-short-black bg

Julie Bean​


Amazing experience with Cornejos builders. From beginning to end- communication was clear as well as expectations. 

Work was 5 star and every member of the crew was exceptional. I would highly recommend Cornejos builders for ANY project or build. 

I will continue to use them and refer them for as along as they are available. Thank you for your beautiful work at such a competitive price!!!!

Daisy Tapia​


Highly observant to detail or changes that others often over look. 

Gives various options on products and communicates in a professional manner. 

I really admire the work ethic.


Ronda Welker​


We couldn’t have asked for a better contractor to work with than Alex. 

We were needing our home remodeled in a very short window of time and Alex and his crew were always on schedule and in touch with us throughout the whole remodel. 

We would definitely use them again.

A Home Improvement Contractor Who Truly Cares

Take advantage of the best perks of working with someone who’s always a step ahead of the industry. Here’s what to expect.

Your home improvement project will be ready according to the schedule. If anything happens, we’ll let you know in advance.

Get the best materials and finishes for your home, all at a premium price that you won’t find anywhere else.

You’ll have access to everything that happens with your project, daily logs, progress pictures, and your own project manager.

Live Your Best Life in a home that keeps on getting better

(takes 1-2 min)