If the wheels touch the floor and it is "being pulled" then a car is classed as a trailer and does not need tax MOT or insurance.

Are the pics below a Capri with a Car behind it or is it a Capri with a trailer ?

It is a Capri with a trailer !

(Why are there so many Capri trailers ? - lol)

What it does need to be though, is in a condition that is "safe to be on the road" and if the "trailed" mass is over 750Kg it needs to be "braked" !