I have the car carrying version of one of these because "old-man" and can load on my own.
https://www.youtube.com/watch?v=DJyrLJuL_qg
Wasn't cheap though ~ $10K AUD but it tows like a dream and has a payload of 1320 kgs
Has been self built for around $7K AUD for steel, airbags and control equipment and registration.
Is open deck but does have the ali front to it which protects the car from road debris
European based but you could also look at these ....
www.turatello,co.uk but I suspect you'd be better off seeking USDM trailer