I'm booking a 1 week rental in LAS and can get either a Premium at $177 or Luxury for $290.

My question is does anyone know what sort of cars I would have to choose from in either of these category's?

Or even if you think it would be possible to book the Premium and then when I get to the lot tip the guy a few bucks for an upgrade to Luxury?

Any help much appreciated.

(Used to be Hertz loyal but these Alamo prices are a quarter what Hertz charges!)

Thanks.