About Us

About Us

Statement From Our Founder

Since opening the Law Offices of Marc Grossman in 1998, it has become my life’s primary privilege and honor to serve so many in our community through our Law Firm.  I have done and do so with both the pride and the burden of carrying on a family legacy of trust, integrity and respect.  I can trace this legacy back to my grandparents who settled in Ontario nearly 100 years ago.  As a small child accompanying my father around town 50 years ago, folks would stop to tell me about my wonderful grandparents who had been so helpful to them and who had such a positive impact on their lives.  That sense of awe and admiration drove me even more 30 years later as a young attorney when folks around town would stop my kids to tell them how much my father had helped them through difficult and challenging times.  Before passing in 2021, my father was an Elder Law Attorney and devoted his professional life to helping local clients with their estate and end of life issues, at a time when they needed someone they could trust. 

I grew up in Upland, attended Upland High School and even substitute taught there during law-school. I have raised my children in Upland where they are the fourth generation of my family that will have both the pride and burden of a good name in the community.  In addition to my proud local roots, I am also guided by my Jewish faith to fulfill the principal of “Tikkun Olam” which means it is my duty to engage in various forms of action to repair and improve the world. I do this by bringing Trust, Integrity and Respect to the way I provide professional services and in this way I also honor my family’s good name and reputation which is my duty to bear.
Why Free Consultations? It is my business philosophy and promise to every person who walks across my door to give them the same advice I would as if they were my brother, sister, best friend, or family member. Unlike firms who only practice in a single practice area, it has been my business practice and philosophy to create the biggest window of opportunity for helping people to give them the best advice even when it is contrary to my own best interest.  Where there are alternate, cheaper or other paths to deal with a situation, I will always do my best to help my clients explore whatever is in their best interest.  Clients are often astounded when I provide them better or alternate ways of solving their problems other than by hiring me.  As rare as it is in the current and local professional environment, putting my client’s interests first is how we ensure that the legacy of Trust, Integrity, and Respect will continue. 

Our Vision

By bringing Trust, Integrity and Respect to the way professional services are provided, Marc honors his family’s good name perpetuating these traditions.



It has been our privilege and honor to serve so many in our community with their most important matters through our Law Firm and Brokerage.



We provide the biggest window of opportunity for helping people to give them the best advice even when it is contrary to our own best interest.



Our clients are our principals and our inspirations, who's goals become our goals and who's fights become our fights.

Hector Rafael Castaneda

REAL ESTATE BROKER (27 years experience)


Buyer’s agent.Listing agent.Foreclosure.Legal, Divorce, Trust, Probate, Landlord.

Hector Rafael Castaneda was born and raised in Upland, CA. located in the west end of San Bernardino County Area. He is the youngest child of Carlos and Irma Castaneda, who immigrated from Chihuahua, Mexico to California in the mid 50’s. Mr. Castaneda attended local schools, and graduated from Upland High School. He then attended New Mexico State University (NMSU) in Las Cruces, NM, and graduated with a Bachelor of Business Administration in Sale Marketing. While at NMSU, he was President of the Hispanic Business Student Association, Head Coordinator of the Special Olympics @ NMSU, and member of Delta Sigma Pi, professional business fraternity.

Mr. Castaneda has been in the Real Estate industry since 1995. He enjoyed many years of successful stewardship, mentor-ship, and recruiting as a Realtor for local Brokers. In 2004 he was asked to steer the helm as a Branch Manager of a local Century 21. He became the youngest Manager in the region for that system. During his tenure he was able to propel the branch from #13 to #3 in the region. He was also introduced to radio advertising as the “on air” character and personality, “Hectorthehomefinder”, on Wild 96 FM and KDAY 935.FM.

In 2007 Mr. Castaneda took the helm at MGR Real Estate in Upland, CA. He has been quoted as saying: “”We are what we repeatedly do. Excellence, then, is not an act, but a habit.” His focus is to propel the staff at MGR Real Estate into new heights of their own success. As a full time manager, he is available to his staff over 45 hours per week. He is persistent that his agents will be the most professional, knowledgeable, and supervised in the Inland Valley.

2013 brought Mr. Castaneda as a Broker Associate at Keller Williams in Rancho Cucamonga, CA. In this capacity he represents clients not only statewide, but nationwide. In addition, he administed and consulted on property rehabilitation, sales and leasing of over 2000 properties in over 40 states for a non-profit organization called Homestrong USA. Learn more about what they do for Veterans nationwide at www.homestrongusa.org.

In January 2016 Mr. Castaneda took the helm at Tarbell Realtors in Corona, CA as Managing Broker. In addition to Recruiting, Training, and Retaining the Finest Agents in the Inland Empire, he still actively maintains as an active Listing/Buyers Broker.

Today, Mr. Castaneda proudly holds the leadership position of Managing Broker for Grossman Real Estate in Upland, CA. They specialize in real estate services dedicated to Probate, Trust, Dissolution, Divorce, and any properties with lien or title issues.

Mr. Castaneda speaks fluent Spanish. He continues to be active in community events, Church, exercise groups, and enjoys acting in community theater. He lives locally raising his son Evan.

Dehaven Leniger

Specialties: Listing agent, Buyer’s agent, Divorces, Probate, Trust and foreclosures
Dehaven Leniger was born in Los Angeles, CA and grew up in Pismo Beach, CA. Ms. Leniger relocated to the Inland Empire in 1991 where she had two children and now has five grand children as well. 
Going on a quarter century experience, Dehaven  has worked in the Real Estate industry since 1999. She started her real estate career working with title learning the ins and outs of real estate  transactions.
This experience made it easier for Dehaven to know how to successfully get real estate deals closed without problems.  In 2011, Dehaven left title and started working as a Realtor with Century 21 Beachside in the city of Upland where she remained until 2015 when she moved to Keller Williams where she honed her negotiating skills and established herself as a closing leader in her office.
In 2016, and for the following four years, Dehaven was asked to be part of the Agent Leadership Counsel (ALC) for top selling agents. Along with sitting on the ALC, Dehaven also began volunteer service for the Grievance committee at the Citrus Valley Association of Realtors where she served for three years.  In 2018, Dehaven was elected to the Board of Directors at the Citrus Valley Association of Realtor, where she served a term of two years as a Director while also serving on the Professional Standards Committee. Prior to Covid, Dehaven also taught realty classes at CA RealtyTraining where she was able to bring her passion for real estate to the next generation. 
Dehaven brings her passion for service to her family, community and clients who have real estate needs.  Dehaven loves traveling, going to the gym, spending time with family and making memories and having experiences.

Our team of expert Attorneys and Brokers includes the most experienced, trusted and respected professionals in our community.  Our Consultations are always free and your best interest is always our only concern.

© 2023 Grossman Real Estate.