About

A boutique advisory, built around trust.

Don Heller Group is a Los Angeles luxury real estate and new-development advisory operating under Christie's International Real Estate. Over a career representing more than $1B+ in transactions, Don has advised buyers, sellers, and developers across the city's most sought-after neighborhoods.

Meet the team

The people behind every transaction

Don Heller
Principal | Executive Director, New Homes Division
DRE #01198240
Don Heller entered real estate in 1996 after a 20-year career as an international CEO in the healthcare and computer automation arenas. He moved to Los Angeles more than three decades ago, and it is the relationships he built through each opportunity that allowed him to grow his business through referrals. Don has gained knowledge from practicing real estate throughout the Los Angeles basin, and has been repeatedly recognized for his success in new developments — particularly through his history of continuously accelerating absorption speeds, surpassing sales records, and consulting from land acquisition through every phase of development, marketing, and sales.
It is his passion for people, his commitment to seeing each party walk away victorious, and his belief that there is always a solution to every challenge that has defined his career. Grown from a passion for development, Don has sold more than 90 new-construction condominium projects and single-family homes, personally developed and built more than a dozen luxury homes and multi-family properties, and completed more than $2 billion in sales.
In his limited off hours, Don has a passion for travel, golf, and his family.
Tammie Chi
Luxury Estates Agent
DRE #02140659
Tammie Chi is a distinguished and seasoned real estate broker with a rich professional journey. Tammie kick-started her career as a consultant in a Fortune 500 company, bringing strategic insight and business acumen to every project. She then ventured into the dynamic world of startups, gaining expertise across business development, marketing, product management, and operations. It was a personal milestone — the purchase of her own home — that ignited Tammie's deep-seated passion for the real estate industry.
Honest and relentless, Tammie tackles each transaction with a combination of refined expertise and meticulous execution. As a resident expert and urban dweller in the Los Angeles real estate market, she thrives on exceeding client expectations by actively listening to their unique needs and ensuring exceptional service from beginning to end.
A global citizen fluent in both English and Mandarin, Tammie has resided in San Francisco and Seattle before settling back to her roots in sunny Los Angeles. Leveraging her global connections and the extensive network of the Don Heller Group, she provides clients with unparalleled market exposure — locally and internationally. Beyond real estate, Tammie enjoys exploring new restaurants, savoring fine wines, working out, and spending time with family.
Sookhee Cha
Luxury Estates Agent
DRE #02169254
With international real estate experience across California, Japan, and Korea, Sookhee Cha brings a unique perspective to her clients — along with a pool of international buyers to prospective sellers. Understanding that no two property deals are alike, Sookhee is committed to serving the unique needs of her clients while navigating today's ever-evolving real estate market.
As a resident of Yorba Linda, Sookhee enjoys building a life with her husband and three children — along with four chickens and a bearded dragon named Ned.
Dustin Lee
Luxury Estates Agent
DRE #02215700
With a strong foundation in science and a degree from UC Berkeley, Dustin's analytical mindset and keen observations have been invaluable assets in the world of real estate. Beyond his academic background, he has always been drawn to the industry, and that passion shines through in every transaction. His natural calm demeanor, coupled with his ability to navigate various situations with finesse, allows him to guide clients confidently through even the most complex deals.
When Dustin isn't closing deals, you can find him on the golf course or carving down the slopes — he has a deep love for competition and the outdoors.
Michelle Adams
Luxury Real Estate Specialist
DRE #02178486
Born and raised in Beverly Hills, Michelle grew up immersed in the world of real estate, with three generations of industry expertise shaping her perspective. Her career began in Washington, D.C., where she studied at George Washington University and worked in politics. While she thrived in the fast-paced world of policy and negotiation, she felt a strong pull back to her roots — helping people find homes and build lasting investments.
With over 200 successful lease transactions and extensive experience in property management, Michelle brings a results-driven, strategic approach to buying, selling, and investing in luxury real estate. Her deep understanding of market trends, combined with a personal, hands-on approach, ensures every client receives white-glove service tailored to their goals.
Whether purchasing a dream home, selling for top dollar, or expanding an investment portfolio, Michelle is committed to delivering exceptional results with discretion, integrity, and expertise.
Lena Nguyen
Real Estate Specialist
DRE #02282305
A Cal Poly SLO graduate with a degree in Marketing, Lena brings a strong foundation in brand strategy, visual storytelling, and client-focused communication to the real estate industry. Her professional background in marketing, combined with a passion for design and architecture, gives her a fresh and modern approach to real estate — one rooted in creativity, integrity, and a deep respect for each client's story.
Ryan Rosh
Real Estate Specialist
DRE #02060001
Ryan Rosh is a Los Angeles–based real estate advisor with Christie's International Real Estate Southern California, specializing in new-construction and Westside luxury properties. With a background in Silicon Valley and experience across both residential and multifamily brokerage, Ryan brings a rare blend of market insight, analytical discipline, and developer-minded perspective. He has been involved in more than $100M in transactions across the greater Los Angeles market.
Ryan is known for his calm, thoughtful approach — focused on understanding each client's goals, offering clear guidance, and making the process feel comfortable and informed. Whether helping someone navigate a move to Los Angeles or explore upcoming new-construction releases, he prioritizes trust, communication, and long-term relationships.
Bridget Reeves
Real Estate Specialist
DRE #0147855
Bridget Reeves brings a unique blend of creativity, professionalism, and relationship-driven sales expertise to real estate. Her career began in the performing arts, where she sang professionally in an a cappella group before attending Metropolitan State University. She later pursued a successful modeling career as a fashion runway model, working in major markets including Denver, Minneapolis, and Los Angeles.
Drawn to the world of real estate, Bridget transitioned into new-home sales and has specialized in luxury multifamily developments since 2006. Over the past two decades, she has represented developers in the sales of luxury condominium communities ranging from boutique mid-rise residences to high-rise developments.
Known for her ability to connect with people, Bridget enjoys building lasting relationships with buyers, sellers, and fellow professionals. She is passionate about helping clients find the home and floor plan that best fits their lifestyle while providing guidance and support throughout every stage of the sales process. Her commitment to exceptional customer service, attention to detail, and seamless execution defines her practice.
Lulu Woldemariam
Real Estate Specialist
DRE #02200722
Lulu Woldemariam is a Real Estate Specialist with the Don Heller Group, partnering with buyers and sellers across the greater Los Angeles market with a discreet, service-first approach.
Sophia Saviss
Executive Coordinator, New Development & Luxury Estates
A born-and-raised LA native, Sophia Saviss found her way to real estate through an innate passion for architecture and development, gaining insight from an early age into the intricacies of the industry. After spending a year abroad at the American University of Paris, Sophia graduated from USC with a bachelor's degree in real estate development.
Throughout her career, Sophia has taken on various roles and gained valuable experience across architecture, acquisition, and asset management. She joined the Don Heller Group as an Executive Coordinator, contributing to high-value transactions and sales within the Los Angeles market.
In her free time, Sophia enjoys socializing with friends and family, playing tennis, and meeting new people. Well traveled, she can offer great tips for the best spots in Saint Tropez and Tel Aviv.
Mariam Malik
Marketing Director
DRE #02036066
Mariam Malik is a dynamic Marketing Director at the Don Heller Group, where she leads branding and marketing for multiple developments and luxury properties. With more than eight years of experience in the real estate market, she has worked alongside top-producing luxury teams. Her background has honed her expertise in digital marketing, social media strategy, and property branding, allowing her to craft compelling campaigns that drive engagement and sales. Mariam's strategic approach, combined with her keen eye for design and market trends, ensures that every property is showcased at its finest.
When she's not crafting innovative marketing strategies, Mariam enjoys staying active through hiking, yoga, and skiing. She also loves hosting dinner parties and spending quality time with her family.