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The Marshall G4 Team was founded in 2018 by cousins Joey Oliva and John Marshall.  Joey and John are both 4th generation Peninsula/San Francisco area Real Estate Brokers who work at the family business founded in 1959 by their grandfather, Bob Marshall, Sr.  Their partnership was formed on the basis of their market knowledge and loyalty to their individual clients, a Marshall family tradition for four generations.  They work alongside Joey's mom and both their uncles in the San Bruno, Burlingame, San Carlos and San Francisco locations.  Their youthful energy and marketing savvy combine to create a winning team combination that has bringing the Bay Area home for four generations.



BROKER, DRE# 01936757

Joey Oliva was born on the San Francisco Peninsula with real estate in his blood. He was raised in Millbrae, attended St. Robert’s School in San Bruno, and is a graduate of Junipero Serra High School in San Mateo. He also spent his college years in New York City at Fordham University where he graduated in 2005 with a BA in English. He is currently working in San Francisco and the Peninsula and brings deep knowledge of the area to his work in the real estate industry.

Prior to real estate, Joey’s professional career was in advertising and marketing with a focus on the theatre industry. Joey worked for nearly a decade in New York City and Los Angeles selling shows and entertainment using a broad collection of tools and techniques--managing social media campaigns, developing targeted marketing strategies, coordinating print-ad efforts, and writing marketing presentations. Joey’s expertise in this area is invaluable to his clients. 

Born into a family of salespeople, Joey has a lifelong passion for putting on a show. When you are ready to sell your property, Joey will bring his engaging personality and natural showmanship to the task. Joey has the know how to position your property in its best light and convince potential buyers that this is the home for them. 

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REALTOR®, DRE# 02040161

John Marshall was born and raised here on the Peninsula. A fourth-generation Bay Area Realtor, John attended Junipero Serra High School in San Mateo. Upon graduating from Chico State University, John joined the family business, working alongside his aunt, uncle, and cousins in today's fast-paced Bay Area market. With a major in business management, John's expertise in representing buyers and sellers has proven unparalleled, with him having 100% success rate in getting his clients into their desired homes fifteen times in 2017. Combine all this with his hands-on background in property management working with tenants and owners, commercial and residential, he brings a full perspective of the real estate industry to his work. With his keen attention to the current market and competitive business savvy, John's experience and real-estate pedigree combine to give you the best service when buying, selling, or managing your properties.


REALTOR, DRE# 02154573

Andrew Monozon was Born in San Francisco, raised in San Bruno and has lived on Crestmoor Dr since he was brought home from the hospital. He attended John Muir Elementary, Parkside Intermediate School, Capuchino High school, and Cal State Fullerton. He’s a true peninsula native who's been a part of this thriving community all his life.  After a youth full of baseball and football, he found himself intrigued by music in a way that he had never experienced before and began playing guitar at the age of 12. Since then, he’s become a very proficient guitarist and loves playing almost as much as selling real estate. Andrew’s interest in real estate started at a very young age as his grandfather was a beloved Peninsula Realtor, Michael Clifford Monozon. Andrew's grandfather gave back to the community any chance he had and inspired many within this industry. He has always loved living here in the Bay, yes because of the beauty, but more so because of the quality and integrity instilled within our community. His grandfather always said “Integrity is Everything” and he will do all within his power to live up to the standard he has set for him.



REALTOR, DRE# 02131031

Shannon Welch, born in Redwood City, and raised on a farm in Northern California, came from a well-known real estate family on the Peninsula, headed by her grandfather, Joseph Welch, Jr.  “Big Joe” worked closely with Joey Oliva’s great grandmother (Augustine Liberti) and her son-in-law, Bob Marshall Sr. The next generation included Annie Marshall Oliva, her brother Bob Marshall, Jr. and Michael Monozon. Thus, the G4 Team was formed by the four descendants of six elder real estate pioneers.    

With 10 years of commercial property experience, facilitating large projects (retail and warehouses), Shannon brings a wealth of information to her clients because she is also an owner with her family of multiple properties on the Peninsula. She understands how to work with local city departments, navigate the permit process, and negotiate effectively with other agents. Her superpower? Shannon intuitively knows how to manage the many moving parts.     

Shannon’s passion and vision? She has a commitment to honoring the land by connecting dedicated stewards to sustain the regenerative practices of land restoration throughout Northern California. 

Married to Owen Moore, they have two children, a boy and a girl. In her spare time, Shannon spends a lot of time in nature, at Surfer’s Beach in El Granada and in the redwoods. They also love to garden as a family, growing fruits and vegetables.   

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