I want to add my name to my mom's property deed. I am in line for the inheritance of it already but don't want the state to cash in for their usual lions share, should she die. There is no mortgage - title is free/clear.

What makes you think the state will cash in? There is no tax on property left to a child. Maryland Estate Taxes - Inheritance tax

In fact, it might cost more, because if you were to add your name to the deed, that constitutes a sale. For mom to sell the property to you, you would have to buy your share at fair market value. Now mom could take a mortgage from you for your share and then forgive a portion of the mortgage each year.

I strongly suggest you contact an tax specialist and real estate attorney for the real ramifications of this.