If you're talking about the trailers I think you are, you can't pull them with a car. There's the little ones, and that will work with most cars. But if you're thinking a 10-15 foot trailer, nothing less than a truck will do. My dad moved a ton of my stuff in a 10 foot trailer (the size of a small UHaul) with his truck from Buffalo to Boston a couple summers ago.Look at the car rental sites, and see if they rent out trucks. I'm not sure they do, but they might.
Also, what kind of complaints are there? Do they tend to run a little late picking up/delivering? Or days late? Do they have a tendancy to charge you more after they've loaded? Have people said their stuff has been held hostage until they pay added/hidden fees?