Thats when you have to un-hook the trailer and drag it out with the truck then hook it up and load it on the trailer.Also you think you going to be able to drive a 20,000lbs vehicle behine a bard and what not.Then good luck on not getting stuck lol.
It won't work because the top car would hit the cab.Plus it would be alot harder than you think.

If i had something like that then i would have my two car behind it hauling 3 at a time lol.