Assuming he is flying to Hawaii, that would set him back at least $600. That's 12% of his yearly budget. Not to mention the fact that actually living in Hawaii is not cheap, and the article said he does this all winter.
http://www.mrmoneymustache.com/2012/12/15/high-cost-of-livin...
http://www.mrmoneymustache.com/2012/11/18/mustache-on-the-mo...