Sentinel Advisory Group, LLC

Peter Shulla is a financial advisor at Sentinel Advisory Group, LLC with 19 years of industry experience. He holds the Series 63, Series 65, and Series 66 designations. His prior experience includes roles at Northwestern Mutual Wealth Management Company and Commonwealth Financial Network. Shulla also engages in fixed insurance sales as a secondary business activity. Sentinel Advisory Group, LLC provides financial planning and asset management services for individuals and retirement plans, including retirement-plan consulting, plan participant advice, and employer HSA consulting. The firm delivers discretionary managed accounts using asset-allocation principles and modern portfolio theory, along with fee-for-service planning supported by third-party research.

Natalie Gardina is an advisor at Sentinel Advisory Group, LLC with a Series 65 credential and started her career in the financial industry in 2024. Prior to joining Sentinel, she held positions in the hospitality and retail sectors. Sentinel Advisory Group provides financial planning and asset management services for individuals and retirement plans, offering portfolio management, retirement-plan consulting, and employer HSA consulting. The firm uses model portfolios based on asset-allocation principles and modern portfolio theory, with a focus on both retail and employer-focused financial services.

Karly Costanzo is a CFP® with six years of industry experience and is currently with Sentinel Advisory Group, LLC. Her prior roles include positions at Northwestern Mutual Investment Services, LLC and Commonwealth Financial Network. She spends a small portion of her time involved in fixed insurance sales. Sentinel Advisory Group, LLC provides financial planning and asset management services for individuals and retirement plans, offering discretionary managed accounts alongside retirement-plan consulting and employer HSA advice. The firm utilizes asset-allocation principles and modern portfolio theory in its investment approach and delivers both fee-based portfolio management and separate fee-for-service planning.

Nathan Keeling is a financial advisor with Sentinel Advisory Group, LLC, holding the CFP® and ChFC® designations and the Series 63 license, with 11 years of industry experience. His prior roles include positions at Northwestern Mutual Wealth Management Company and Commonwealth Financial Network. Outside of advisory services, he is involved in fixed insurance sales. Sentinel Advisory Group, LLC provides financial planning and asset management services for individuals and retirement plans, offering portfolio management, fee-based advisory services, retirement-plan consulting, and employer HSA consulting. The firm utilizes Commonwealth Financial Network’s discretionary managed account programs and incorporates asset-allocation principles and modern portfolio theory in its investment approach.

Kelsee Guest is a financial advisor at Sentinel Advisory Group, LLC with four years of industry experience. She holds Series 63 and Series 65 licenses and has prior experience at Commonwealth Financial Network, Northwestern Mutual Investment Services, and Trane Technologies. Sentinel Advisory Group provides financial planning and asset management services for individuals and retirement plans, offering discretionary managed accounts through Commonwealth Financial Network’s programs along with retirement-plan consulting and employer HSA consulting.

Michael Harmelink is a CFA® charterholder affiliated with Sentinel Advisory Group, LLC and has over two decades of experience in investment management. Prior to joining Sentinel Advisory Group in 2025, he worked at the State of Wisconsin Investment Board from 2001 to 2025. He also serves as a consultant for Global Advisory Partners, providing corporate investor relations consulting. Sentinel Advisory Group offers financial planning and asset management services for individuals and retirement plans, including discretionary managed accounts based on asset-allocation principles and modern portfolio theory. The firm provides retirement-plan consulting, employer HSA consulting, and uses third-party research and wrap programs to support portfolio construction and rebalancing.

Cary Grunder is a financial advisor at Sentinel Advisory Group, LLC with 35 years of industry experience. He holds the ChFC® designation and Series 63 license. His prior roles include long tenures at Northwestern Mutual Wealth Management Company and its affiliated entities. Sentinel Advisory Group provides financial planning and asset management services to individuals and retirement plans, offering portfolio management, retirement-plan consulting, and employer HSA consulting. The firm utilizes discretionary managed accounts through Commonwealth Financial Network’s PPS programs, employing asset-allocation principles and modern portfolio theory with ongoing portfolio monitoring and tax-harvesting.

Brenton Cashore is a financial advisor at Sentinel Advisory Group, LLC with 16 years of industry experience. He holds Series 63 and Series 65 licenses and has previously worked at Commonwealth Financial Network and Northwestern Mutual in various capacities between 2009 and 2025. Sentinel Advisory Group provides financial planning and asset management services for individuals and retirement plans, offering portfolio management, fee-based advisory services, and retirement-plan consulting. The firm uses asset-allocation principles and modern portfolio theory in its managed accounts and provides employer-focused services alongside traditional wealth management.