Tess Costello is the Co-Founder of SC Real Estate, where she plays a key leadership role in helping clients navigate some of life’s most important financial and personal decisions through real estate. Known for her strong work ethic, thoughtful communication, and client-first approach, Tess is deeply committed to delivering exceptional experiences for buyers, sellers, and investors throughout Northern California.

With a passion for helping people build stability and long-term wealth through homeownership, Tess focuses on creating a smooth and supportive process for every client. She believes real estate is more than a transaction—it’s about guiding families through meaningful life transitions and helping them take confident steps toward their future.

As a co-founder of SC Real Estate, Tess works alongside her husband and business partner, Derek Sandoval, to lead a team built on integrity, collaboration, and service. Together, they have created a culture centered on relationship-building, community involvement, and delivering results that exceed expectations.

Tess is also actively involved in the team’s community outreach initiatives, including programs designed to support veterans, educators, healthcare workers, and other local heroes through specialized homeownership programs.

Whether working with first-time buyers, move-up families, or clients relocating to the region, Tess brings care, professionalism, and dedication to every relationship she builds.

Client-First Approach

Tess believes that real estate is about more than transactions—it’s about relationships. She takes the time to truly understand each client’s goals, ensuring every decision and strategy is aligned with what matters most to them.

Clear Communication
Buying or selling a home can feel overwhelming, which is why Tess prioritizes clear, consistent communication throughout the entire process. Her clients always know what to expect, what comes next, and how their transaction is progressing.

Attention to Detail
From preparing a home for market to navigating negotiations and contracts, Tess is known for her thorough approach. Her attention to detail helps protect her clients’ interests while creating a smoother and more organized experience.

Support Through Every Step
Whether someone is purchasing their first home, relocating, or selling a long-time family property, Tess is there to guide them from start to finish. Her goal is to make the process as stress-free and seamless as possible.

A Team Advantage
As Co-Founder of SC Real Estate, Tess provides clients with the strength of a full-service team, giving them access to trusted professionals, strategic marketing, and a network of resources that support every stage of the real estate journey.

Kyle and Nadine Mosley

"We recently purchased a home in Oakdale with the help of Tess Costello and we couldn’t be happier! From the start, Tess  was incredibly knowledgeable, patient, and dedicated to helping us find our perfect home. She understood exactly what we were looking for and guided us through every step of the process with professionalism and care. Her expertise in the Oakdale market was evident, and she provided invaluable advice that made the entire experience smooth and stress-free. Tess was always available to answer our questions, address our concerns, and provide updates. Thanks to her hard work and commitment, we are now proud homeowners in a wonderful community. We highly recommend Tess to anyone looking to buy or sell a home. Her passion for real estate and genuine care for her clients make them the best in the business! Thank you, Tess!"

Zhenya Vanerwesthuizen

"5 stars all the way!  Tess Costello is an amazing agent! We would give her 10 stars if we could! Her knowledge, professionalism, communication style, positive attitude and contagious energy are unbeatable! She sold our home in no time and all we had to do is absolutely nothing! Shed had a total and complete peace of mind trusting her to do the job and she did not disappoint! We would HIGHLY recommend her to all of our friends, family and anybody who's looking to sell or buy a property. She is an absolute pleasure to work with!"

Jason Garcia

"Derek provided an amazing experience getting us into our home in Fair Oaks. He was detailed in his explanation of the buying process and was amazing at keeping us notified on any updates to our offer. He also took the time before the process started to understand what we were looking for as well as being very sensitive to our budget. Couldn’t have had a better experience buying our dream family home!"

David Gill

"Tess is tremendous to work with. Her expertise and attention to detail are second to none. She was very attentive to our needs and got our home sold even in these tough times."