I was in the same boat...all the major players showed up empty.
However, check auto europe...I just made a reservation thru them, car will be with Alamo. $370 for 8 days, econonmy, Dec 22 to 29, Kona, HI. Note that with AE, you have to put down the full deposit at time of booking, but can cancel up to 3 days before trip with no fees.
https://www.autoeurope.com
Have used them twice for trips in Europe with no issue.
Good luck

wagert, first post? Never heard of the site. Feels like a commercial.

We rented from Auto Europe on our trip to Italy in 2005 and I know other fodorites have mentioned using them for US car rentals.

Auto Europe is legit. It gets mentioned a lot on the Europe boards. I didn't realize that they did US rentals as well, but the company itself is well known.

I not saying the Auto Europe is not legit. I've never seen it mentioned in context of Hawaii. They have no outlets in the island so they are akin to a consolidator and if there are no cars available from hertz, avis, national, etc. why will auto europe find one? It just seems weird to me.

I haven't used them personally so don't know a lot of details, but I believe it's something akin to Expedia or similar - you book through AutoEurope and actually rent through Hertz, for example (just as you might book flights through Expedia and fly through AA).

As to why AutoEurope might find bookings in Hawaii when no one else can, well, that mystery of the travel world I cannot answer. :) But I can't imagine why AutoEurope would need wbpiii to advertise for them; I think he was just sharing helpful information.

AutoEurope does indeed often have some of the best rates in the US. The only thing to look out for is that they sometimes require you to purchase a full tank of gas (and then return the car empty). When I checked with Dollar whom they were putting me with on one such rental, I found that the gas would be charged at something like $7 a gallon or about $125. And since I can never figure out how to end up with an empty tank I figure I'm probably also going to lose another half tank.

Howdy, all. Enjoying the comments. This is also the first time we've used AE in the US....to be honest, it never occurred to us before. A couple of other notes about our reservation:
1) I will indeed be expected to buy a tank of gas and return it empty.
2) Our reservation includes a zero deductibled CDW. There was no option to decline, it was the only option available for this reservation and car class.

Even with the zero CDW charge....I'm looking at $47/day. Over the Holiday Season. In Hawaii. SIGN ME UP NOW!

Once I had a confirmation number from AE, I called Alamo directly. They confirmed that yes, I had a valid confirmation # and car. I then had him check availability of cars for the period I had just rented, nothing available. Then went back to AE site...cars available.

Conclusion...I Have No Idea. But I'll Take It!
And for those keeping score....Post # 2! :)

wagert, that "available / not available" thing is actually pretty easy. AutoEurope's contract with agencies requires them to make so many cars available. So that agency can clearly not have any to rent on their own when much of their inventory is guaranteed to a consolidator.

THANK YOU WAGERT!!!
I just booked my rental car (funny things - exact same dates) in Kona and they were the only one that had cars. I called and confirmed my reservation also. This was just yesterday and I was scared out of my wits I would not have a car.

Now, if you look at their website, the rates in Kona on those dates have over doubled.

Wow, you are my hero for that AutoEurope!!!

I had called every company and local ones on the Island and there was not a single car to be found.

Ok, before someone says they see normal rates, I just went to their website and their rates are back to normal for those dates in Kona.

But, regardless, AE has saved my rear end because I have no idea what it would cost us to take a taxi everywhere on the island over the whole week.