Keystone Family Office Inc.

Overview

Keystone Family Office provides coordinated support for clients managing international financial arrangements, business interests, investments, real estate, trusts, and family wealth. The firm combines local expertise with an international perspective and describes its work as customized to each client’s circumstances.¹

History

The firm reports more than 25 years of experience delivering customized tax and advisory services. Keystone says it remains founder-led, with a long-term strategic vision and an entrepreneurial leadership style focused on aligning its work with client interests.¹

Leadership

Mark Louis Marinzoli is identified in a 2024 FINRA report as Keystone Family Office’s vice president and partner. His responsibilities include accounting, tax, and business advisory work.²

Services

Keystone’s core services include cross-border tax advisory, corporate structuring, accounting, financial reporting, private client administration, regulatory compliance, wealth structuring, and succession planning.¹

Its corporate services support business formation, governance, compliance, taxation, accounting, and banking support. For individuals, the firm provides U.S. tax support for citizens abroad, international reporting, real estate investment assistance, trust and fiduciary services, and non-discretionary wealth-management administration.¹

Keystone also provides strategic support covering payroll, intellectual-property support, immigration coordination, international trade support, and investment and fund support.¹

The firm’s real-estate support may include portfolio management, property acquisition and disposition, foreign-investor compliance, FIRPTA support, rental-income reporting, property-management coordination, and bill-pay services.¹

Its trust and fiduciary work can include accounting, taxation, administration, oversight, and serving as trustee, co-trustee, or protector.¹

What the firm offers

• Investment management
• Tax planning
• Estate planning
• Trust and fiduciary
• Family governance and education
• Administration and bill pay
• Private and alternative investments
• Cross-border planning

Client Focus

Keystone serves individuals, families, and businesses worldwide. The firm also supports global families and organizations through a combination of local expertise and an international perspective.¹

Approach

Keystone describes its approach as founder-led, entrepreneurial, and guided by a long-term strategic vision. The firm emphasizes customized advice, alignment with client interests, and coordination between local knowledge and international perspective.¹

Its wealth-management offering is administrative and non-discretionary. The firm says this work supports asset structuring, cash-flow planning, implementation of financial goals, organization, and reporting while helping clients coordinate their broader financial affairs.¹

FAQs

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  Profiles of Sageworth, Handwerk Multi Family Office, and Collective Family Office, LLC give readers additional examples of firms serving affluent families and owners. Reviewing their stated services and client approaches can support a side-by-side shortlist alongside Keystone Family Office, especially for investment, fiduciary, administrative, and family governance needs.

Sources

1. Keystone Family Office
2. FINRA BrokerCheck report for Mark Louis Marinzoli

Claim or correct this profile

This profile is a factual summary written in our own words from public sources. It is for information only. It is not an endorsement, rating, ranking or recommendation, and it is not investment advice. MultiFamilyOffices.com is not affiliated with the SEC or with this firm unless stated. Form ADV figures are self-reported by the firm.