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Our People

Roger A. Delisle, Jr.


Managing Director & Commercial Broker

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Roger has been a commercial real estate broker for twenty years. His specialties include national retail leasing and commercial investment sales.


Roger's clients include:  QuickChek Market, LA Fitness, Golds Gym,  GNC, CVS Drugs, Starbucks, Taco Bell, 7-Eleven, Dunkin' Donuts, Lowe’s Home Improvement, Checkers and All Island Pet Supplies, as well as numerous shopping centers, apartment buildings, and office buildings.


Roger earned his MBA from Southern New Hampshire University and his BA from St. Joseph's College. He is a CCIM Designee.

Terence McMahon 

Commercial Sales Associate

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Terence has been with our team for over five years. Terence handles the leasing of commercial retail properties for prospective tenants.


Before joining Island Associates, Terence was an accountant for 25 years. Terence is a graduate of SUNY Old Westbury.

Larry Densen

Commercial Sales Associate

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Prior to coming to Island Associates, Larry worked for Exit Reality as a Licensed  Commercial Sales Associate and Ideal Mortgage Bankers as a licensed Loan Officer and team leader.  From 1979 to 2000, Larry held many positions within WorkSafe Industries. He eventually rose to the position of Chief Executive. During his time in this role, Larry purchased and sold buildings and factories. In addition, he negotiated leases from both sides of the table.   


Larry is proud to be affiliated with the local non-profit which helps children with life-threatening illnesses.

Martine Gelsomino

Executive Assistant

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Martine has been with Island Associates Real Estate for 23 years. Her role includes supporting the president of the company and our commercial agents in all aspects of property research, tenant and landlord relations, tenant and landlord communications and correspondence. In addition, Martine assists with the day to day operations of the office.

Martine graduated from Dowling College, where she earned her Bachelor’s Degree in Business Administration with a Minor in Italian (Martine is fluent in Italian). Prior to joining Island Associates, Martine worked in the retail industry.

Devin Muller

Marketing Administrator

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Devin manages our property listings, website content, media, marketing, social media outlets and various office operations.


She has worked in the administrative field for over 20 years; the last seven of which has focused on website management.

Robert Monahan


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Rob, a former partner in the Carle Place law firm of Monahan & Sklavos, PC, advises and consults our brokers and their clients on all aspects of commercial real estate. 


Rob is a graduate of Iona College and St. John’s University School of Law.


Prior to joining Island Associates, Rob was practicing real estate law with an emphasis on commercial real estate transactions and real estate development on Long Island.

Christopher R. Mayor


Commercial Sales Associate

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Chris has 25 years of experience in commercial development of properties. He has been involved in development projects for multi-family, retail, industrial and office space.


Chris' clients include: Allstate, Montessori School, Dunkin' Donuts, 7-eleven, and many other national retailers. Chris represents both landlord and tenants in lease negotiations for new site locations.


He is Commercial and Investment Real Estate Certified and CIREC designated.

Diane Ferraro

Property Management

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Diane has over 30 years experience as the managing director of commercial and residential properties. She is a licensed Real Estate Agent.


Diane has been the Property Manager at Island Associates Real Estate for the past 15 years. She is responsible for all aspects of leases (new and renewal), income, expenses, vendor contract renewals and budgeting for 15 commercial properties, two office buildings and an apartment complex.

Lisa Sloggatt

Property Manager Assistant

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Lisa graduated from Hofstra University with a degree in Community Health. Prior to working at Island Associates, Lisa spent 13 years as an Account Manager for a healthcare management company. 


At Island Associates Lisa schedules and organizes tenant and client calls, maintains accounting duties and functions, and processes accounts payable checks and rent payments.

John Gilmour


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John is a hands-on financial executive providing strong combination of business acumen, Information Technology, and executive leadership to drive profit growth, and reduce costs in manufacturing, professional services, and contracting environments. He is skilled in identifying and resolving complex financial and organizational issues.

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