I have rented several cars through Priceline. There are a few things you can do, though nothing's guaranteed. You won't have any luck at all going through Priceline - they stick hard and fast to their no change policy. For instance, I rented in Florida in West Palm Beach with a dropoff in West Palm. My plans changed and I wanted to drop in Tampa. Even though the rental company wouldn't have charged me a drop fee, Priceline said "no way". I had to rent a new vehicle and eat a day's rental on the West Palm rental. Don't bother with the 800 number to the rental company either. They will see your reservation is from Priceline and will give you the "we can't change it" line. Your best bet is at the rental counter. Drag your spouse, kids and luggage up to the counter. When they announce the vehicle you reserved, motion to your family and ask if there are any upgrades available. Appeal to emotion. What you get will be completely based on available inventory. Most agents tend to be sympathetic, particularly if it means more $$$ to the rental firm. A plus you have working for you is that you have reserved a convertible, a car normally in high demand. You don't mention where you are going, but it does mean something if your destination is a warm weather spot like south Florida, etc. (Of course, if it's Minnesota in December, good luck :) ). What I am saying is the rental agency may be glad to have that vehicle back in inventory since they may be able to easily rent it. As a rule of thumb (for me at least), it is very risky to rent a convertible for more than two (max. three) passengers for the reasons you are experiencing: they have little trunk space. I hope everything works out for you. Good luck
