Mary Kay Foss, CPA Mary Kay specializes in handling complex trusts and individual tax planning. She goes above and beyond the compliance work to understand the personal issues faced by her clients and how they affect retirement planning and trust administration and funding. In addition, she teaches classes for CPAs and other financial professionals about retirement planning and estate planning. Mary Kay has 30 plus years of public accounting experience providing planning, and tax preparation services for complex estates, trusts and individuals. She also works closely with fiduciaries to assist with trust funding and reporting to beneficiaries.