Following up on Tuesday’s post, The Costs of Estate Tax Dithering: Forbes, How to Protect Your Family From Estate Tax Uncertainty, by Ashlea Ebeling:

An Illinois woman inherited not quite $100 million this year. Estate taxes could consume 53%, 45%, 16% or none of it, depending on whether the federal and/or Illinois estate taxes–which both lapsed on Jan. 1, 2010–are reinstated retroactively. “It’s wacky to have so many scenarios and not know what the tax is,” complains Richard A. Lang, a Chicago partner of McDermott, Will & Emery representing the estate. …

President Obama and most Democrats want to restore the estate tax retroactively to its 2009 state–meaning $3.5 million per estate would be exempt, the tax rate would be 45% and all assets would get a step-up in basis. Republicans want a higher exemption and lower rate. When and how this gridlock will end is anyone’s guess. After all, rational folks (including most estate planners) had assumed the pols would cut a deal before the tax expired. Complicating matters: Any retroactive tax is likely to face an epic court fight from rich heirs, perhaps including those of Texas pipeline tycoon Dan L. Duncan, who died in March with (we estimate) $9.8 billion.

You need to be careful even if you don’t have as much as Duncan. Here are some tips.