If anyone is wondering how you attain VIP status this is the email I received back from National.

Thank you for your email. The Emerald Club program is available to all National customers (business or non-business) who want to experience fast rental transactions, have a choice of vehicles, and earn rewards for their National rentals. Renters are automatically upgraded to the next tier at any time of the year. Our Emerald Club Executive VIP tier is for close friends and associates of our CEO and founder, Andy and Jack Taylor. To achieve this status of rental service with us; you would have to be invited personally by our founder or CEO. Only 0.1 percent of our customers are members of this exclusive tier. Their benefits are exactly the same as all other tier levels of the Emerald Club with the exception of local delivery service. I hope I answered your question. If you should need anything further, please email us.