question: can i have two concurrent, overlapping reservations? For 2 days, 3 hours at IAH, I can book a EXAR for $54, but am nervous about what i'd get and if i can use gold choice to switch it out. I have an ICAR reserved for the same period for $69...can i keep that, make an EXAR, then cancel the EXAR if i get assigned a crummy car when I arrive? Is there any kind of penalty or anything since my credit card is on file? Thanks!