I learned a long time ago that a low trailer is the best way to go. However, if you have to put it in a truck, have a lot of help, or drop the rear tires into a low spot in the ground where the tailgate is. at most, two feet off the ground.
The slope down my driveway combined with the upslope in the street is a perfect spot for loading my bike in the back of the truck. Getting high centered as you go from the ramp to the truck bed is not a fun deal!
Bare