I went to Hotwire and plugged in some dates for a rental in the city that you were looking for... the rental car rates looked fantastic!
I saw a minivan for $24.99 per day... when I clicked on it... it said we're sorry the rate has changed, when I went back (clicking my back browser button to check some more of the prices).. it now showed the minivan to be $137.95 per day!!!!
So I decided to check a compact car it showed 11.95 per day, when I checked rates for the dates that I had plugged in it again said that the cost had changed... it went up to $70 per day!
So I went to the Hotwire Help Center link and selected car rental searches and booking and then selected the link for information on pricing, rates, mileage and insurance and then the question How do I get the sample rates that I saw on your newsletter or on the site. I wanted to find out if the rental car promotions that show were available at all.
The response from the Hotwire car rental site was
The rates that we show in our newsletters and on the site are examples of rates that other Hotwire customers have recently booked, not guaranteed prices.
It's not clear whether or not those prices were prices that other Hotwire customers had booked in that city recently, or if they were prices that had been booked in the past (and how far in the past) and in a different city (and what city?)
I'm sorry that I'm not able to help you find those great rates, but I hope that I've answered your question.
Pages from this site, relating to this topic:
Using Booking Sites
Tips on finding Car Rental Specials
Tips on Finding Last Minute Deals
PrePaid Car Rental