So last night at midnight, I again found myself standing around an empty rental car lot, with a confirmed reservation but no car available. This isn't the first time, and if you travel much, it's happened to you too.

An even more common but less severe problem comes when the car tyoe you've reserved is unavailable, and you get the "free upgrade" to a full size, an SUV, or a minivan. Fine sometimes, but there are times when you want or need the reserved vehicle, for better gas mileage, for easier parking, for better handling on snow.

What do you seasoned travelers do to minimize this risk?

I understand why it happens. With no deposit and no penalty for no-shows, it's hard for the car companies to manage their fleets. But since these policies are pretty much universal, at least in the US, knowing why still leaves me standing around the empty lot.

It's often not convenient to try other companies, not once you've already been shuttled to the lot, and if you've booked a god rate, you're likely to pay a lot more with someone else as a walk up.

Last night was with Alamo, but before you tell me it's my own fault for using a cheapo company, I'll note that the lot is shared with National, and there were plenty of Emerald Aisle folks also standing around car-less. I've had the no-car problem with Avis (Preferred service) as well; I don't think it's happened to me with Hertz Gold, but I have gotten to my Hertz numbered space to find the unwanted upgrade.

So is there a solution? How do you avoid this, and how do you handle it when it does happen?