Hi,
Just a thought or two---
Most "toy haulers" are not built to haul things as heavy as cars, Jeeps etc. They are designed to haul "toys". [Quads, off road bikes, etc.] Your Z car may not have enough ground clearance to load and off load easily.
You are right about double towing. However, we have double towed a Jeep Liberty for a year and a half, [10,000+ miles] been passed by dozens of highway patrol cars, in mahy states, and never once been pulled over. However we are not trying to convince anyone to do it, But except for one case, we heard about in Penn. any one else that was stopped was simply told to unhitch the car from the trailer and let the wife drive it. JOHO
Oh, welcome to the forum.