My 20' enclosed trailer weighs about 3500 lbs empty and uses dual 5K+ lb torsion axles. My trailer has a 4" drop with dove tail so even low slung vehicles will not have a problem with the break over angles.I have a door up front allowing me to store access additional items when the vehicle is loaded.
If you are hauling a 2-door car, you will want an escape door to be able to open the car door enough to get out. If your car is taller than 6', you will want a trailer with additional height (typical purchased in one foot increments}. Make sure the tongue length is 4' or more so tight turn or driveway dips do not allow the trailer and RV to touch.
I use wheel nets/bonnets to tie down the car rather than trying to tie to frame or suspension.