MainStreet Investment Group L.L.C. Wealth Management - Home



Welcome to MainStreet Investment Group!  We are so glad you found your way to our site!


MainStreet Investment Group was founded on the principles of integrity, superior client service and a commitment to accountability.  Our mission is to create a level of service that exceeds our client’s expectations.

If you are retired or close to retirement, it may be beneficial to work with an advisor who has a definable risk management plan, an investment management process and a level of service that exceeds client expectations.  It may be time to look at your portfolio and examine your investment objectives and transition from wealth accumulation to preservation and income.

MainStreet Investment Group has two office locations:  Tomahawk, WI and Thiensville, WI.  Please browse our site, and feel free to call either Randy Plantenberg or Rich Nagel to schedule a complimentary consultation to see what makes our approach unique and to discover new possibilities for your investment portfolio and financial planning needs.


Randy Plantenberg is located in our Tomahawk, WI office; Randy can be reached at (715) 453-0722.

This location’s office hours are Monday through Friday, 8:00am to 4:00pm.


Rich Nagel is located in our Thiensville, WI office; Rich can be reached at (262) 478-3000.

This location's office hours are Monday through Friday, 8:30am to 4:00pm.




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