According to this article - http://www.guardian.co.uk/worldlatest/story/0,,-5708939,00.html - she rented the condo but never used it.
Two possibilities, she rented the condo as a safe house after the murder but thought better of it since it could be traced to her name.
She rented the condo as an excuse to keep people from looking for her and the kids or finding his body. We're on vacation so we won't be around John List type move.
She rented the condo in anticipation of a family vacation, and it coincided with the actual murder.
She might have figured that since the kids were told they were going on vacation, she'd just follow thru with that.
I can't imagine what happened in that house??? Don't misunderstand me...I'm not an advocate of killing husbands.
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