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BEST-IN-CLASS, DESIGN-LED REAL ESTATE DEVELOPMENT

Leviathan Development is a leading investment and development firm with over 30 years of experience in all phases of the development lifecycle. Guided by Founder and Managing Partner Allison Greenfield, Leviathan specializes in high-caliber, design-driven projects. Leviathan consistently surpasses investor and community expectations, delivering results that are both impactful and enduring.

With a commitment to sustainable and context-sensitive design that harmonizes each project with its environment, Leviathan leverages over 30 years of extensive expertise across the entire development cycle. The firm has successfully navigated every major real estate asset class, exemplifying unmatched expertise and an unwavering dedication to achieving the highest standards and outcomes.

OUR TEAM

Allison Greenfield

Founder & Managing Partner

Colin Carby

Director of Development

Glenn Guthiel

Director of Construction

Karla Rooks

Director of Architecture & Design

Alexei Siniakov

Director of Finance

Tathiana Rosado

Public Relations Advisor

Ashley Spitz Hamaoui

Marketing Advisor

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Allison Greenfield

FOUNDER & MANAGING PARTNER

Leviathan Development is a leading investment and development platform guided by Founder and Managing Partner, Allison Greenfield.  Leviathan specializes in high caliber, design-driven projects that consistently surpass investor and community expectations and delivers results that are both impactful and enduring. With a commitment to sustainable and context-sensitive design that harmonizes each project with its environment, Leviathan leverages over 30 years of extensive development experience across the entire development cycle. The firm has successfully navigated every major real estate asset class, exemplifying unmatched expertise and an unwavering dedication to achieving the highest standards and outcomes.

Allison Greenfield, the driving force and principal behind Leviathan Development, brings over 30 years of intensive experience in the acquisition, development, construction, and operations of real estate investments. Launching her career in Manhattan’s highly competitive real estate market, Greenfield co-founded Oz Holdings, LLC in 1995, where she focused on unlocking the potential of undervalued assets through innovative renovation, construction, and marketing strategies.

A Partner and Chief Development officer at Lionheart Capital for 20 years, Greenfield  played a pivotal role in every stage of the investment lifecycle, with a particular focus on operations, design, construction, and marketing. Her responsibilities include the implementation of development and repositioning plans, with a specialization in development and construction activities.

Greenfield’s portfolio includes several placemaking projects; including the Ritz Carlton Residences, Singer Island; the Ritz Carlton Residences, Miami Beach; the $1 billion Lakeside City Center redevelopment in Sterling Heights, MI, and the much anticipated Mirai Miami Design District by Kengo Kuma. Greenfield is known for her collaborations with elite architects such as Piero Lissoni and Kengo Kuma, both widely regarded as top-tier figures in global Architecture and Design. She has been instrumental in bringing their visionary residential and mixed-use projects to the U.S., working closely with them to achieve their ambitious architectural goals.

Complementing her business acumen, Greenfield is also a trained architect, having studied Architecture at Parsons School of Design and earned a bachelor’s degree in History from Barnard College/Columbia University.

Colin Carby

DIRECTOR OF DEVELOPMENT

Colin Carby is the Director of Development for Leviathan Development Group.

Carby has 20 years of real estate experience developing large scale mixed-use, hospitality, residential, retail and commercial projects in North America, Middle East, Asia, and the Caribbean markets.

Since 2002, Carby has represented entities, such as LVMH, Dubai World, Capital Partners, Midtown Miami, City of Miami, and Bank of America, leading global acquisitions, pre-development due diligence, master planning, and full cycle development management initiatives, which yielded several million square feet of lifestyle communities.

In 2020, Colin joined Lionheart Capital to redevelop several large scaled assets, such as Lakeside Mall in Michigan, which is a 94-acre master planned initiative.

Mr. Carby received his B.A in real estate development at Georgia State University in Atlanta, GA.

Glenn Guthiel

DIRECTOR OF DEVELOPMENT

Glenn Gutheil is the Director of Construction for Levithan Development Group.

Glenn has over 30 years of Architecture, Construction and Development experience managing large scale mixed-use, hospitality, residential, retail, and commercial projects throughout the continental United States.

Prior to joining Lionheart Capital, Glenn was the President of Lenox Development a Florida licensed General Contractor and Consulting company. Glenn has represented entities which included CBRE, Midtown Equities, Laval Management, Urban X Development and Matthews Southwest leading design, construction and project closeout initiatives which yielded several million square feet of mixed-use assets totaling over $3 billion dollars.

In 2022, Glenn joined Lionheart Capital to provide substantive construction feasibility studies, construction cost analysis and to direct all design and construction related projects.

Karla Rooks

DIRECTOR OF ARCHITECTURE & DESIGN

Karla Rooks is the Director of Architecture and Design at Leviathan Development Group. Rooks comes from architectural and construction background before joining Leviathan l, having worked at architectural firms for 26+ years and 3 years at construction companies mainly in high end residential and hospitality projects.

Her work has taken her to South America, Central America, Caribbean and the Middle East in which she participated in high end hospitality and multifamily residential projects.

Rooks holds a Bachelor’s degree in Architecture from the University of Zulia and a Masters in Architecture from the University of Cincinnati.

Alexei Siniakov

DIRECTOR OF FINANCE

Alexei Siniakov is the Director of Finance at Lionheart Capital and brings over 15 years of real estate finance and capital markets experience, having been involved in over $1.5B of transactions throughout his career including property acquisitions and corporate-level debt financing. At Lionheart, he is responsible for investment analysis, financial modeling, and investor relations.

Alexei started his career as a Corporate Finance Analyst at Whiterock REIT (TSX:WRK) a publicly traded Real Estate Investment Trust in Toronto which was later acquired by one of the largest real estate companies in Canada, Dundee Real Estate Asset Management (TSX:DRM). After several years at Whiterock/Dundee and obtaining his MBA, he decided to pursue a Wall Street career in Equity Research covering public REITs; first at RBC Capital Markets, the investment banking arm of Royal Bank of Canada, and subsequently at SunTrust in New York.

Following five years in banking, Alexei returned to real estate as a Director of Capital Markets and FP&A at Kite Realty Group (NYSE:KRG) where he was responsible for structuring debt financing transactions and corporate financial modeling including KRG’s $7.5B merger with Retail Properties of America (NYSE:RPAI). Alexei was later promoted to VP by assuming additional responsibilities of underwriting acquisitions of shopping centers with a particular focus on Sun Belt markets which inspired him to relocate to Miami.

Alexei holds a Bachelor of Commerce in Finance & Economics from the University of Toronto, and an MBA (Dean’s Honor List) from Richard Ivey School of Business at Western University in Canada. He is also a CFA charterholder.

Tathiana Rosado

PUBLIC RELATIONS ADVISOR

Tathiana Rosado, the President and vivacious force behind Ciao Studio, brings her signature touch of creativity, authenticity, and boundless passion to the world of PR. She’s not just rewriting brand stories; she’s crafting a compelling narrative of her own.

With over two decades of experience and a fiery passion for blending traditional and unconventional PR, Tathiana stands as an established leader who embodies confidence and unshakable self-belief. She’s recently been hailed as one of the top PR experts fueling Miami’s explosive growth by Business Insider. She embraces risks with the understanding that true worth lies beyond the outcomes. “It’s about crafting from the heart and having the courage to make it happen.”

Ashley Spitz Hamaoui

MARKETING ADVISOR

Ashley Spitz Hamaoui plays a pivotal role in Leviathan Development Group’s diverse portfolio. Ashley oversees the marketing, public relations, events, branding, advertising and partnerships associated with Leviathan’s myriad of projects from luxury branded residences to commercial shopping centers and malls to public companies.

Her transformative impact in luxury real estate is evident through projects like The Ritz-Carlton Residences, Miami Beach, and The Ritz-Carlton Residences, Singer Island, Palm Beach. What sets her apart is not just her real estate expertise, but also her ability to orchestrate special events that have featured luminaries like Martha Stewart, Dwayne Wade, and Lee Schrager. These high-profile gatherings not only elevated Levithan Development Group’s brand but also created unforgettable experiences for their audiences.

Ashley’s multifaceted career extends to the commercial real estate side, where she has applied her expertise to properties such as Lakeside Mall and Manassas Mall. Having also served as CMO for BurgerFi and successfully guiding the company through the IPO, Ashley’s accomplishments in taking companies public add another layer to her already illustrious career. She continues to shape the company’s future with her prolific contributions, showcasing her profound influence on both luxury and commercial real estate marketing.