The U-Haul trailer worked out great. Thanks for all of your advise. My car has a modest spoiler, and the he car went right on with no clearance issues and only 1 layer of blocking where the ramps touched the ground that probably weren't necessary. The included tiedowns worked great. The trailer towed very well.
The only issue was that the car stopped running just before we loaded, so we had to crank the car up the ramps a few inches at a time with a ratchet strap. Of course, in the old days, I would have detached the trailer, chocked it, tied a rope between the car and the trailer ball, and pulled the car on with the van. What could go wrong?
The best part was that when we got to our destination, we unloaded, drove a couple of miles to the local U-Haul dealer and gave the trailer back, saving 6 hours of driving with a trailer, substantial tolls, and lots of gas.