This from White House Dossier
The decision by First Lady Michelle Obama to leave on schedule for her two-week Hawaii vacation and not wait a few days for her delayed husband will probably cost taxpayers more than $63,000 – and possibly well in excess of $100,000 – in additional expenses, according to a White House Dossier analysis.
President Obama was supposed to depart for Hawaii Saturday, but decided to stay in Washington until Congress finishes its work for the year. He departs this evening. But Mrs. Obama chose to leave without him Saturday, taking their two children and the dog along with her.
Mrs. Obama’s decision to go without the president forced her to take a separate plane, meaning two flights instead of one were needed to ferry the First Family to their vacation destination. Unless for some reason her plane was headed to Hawaii anyway, her trip involves substantial additional costs.