A frames for car towing

This link will lead you to a couple of threads on the subject.

https://www.caravanclub.co.uk/club-together/discussions/information-technical-tips-advice/motorhomes/towing-a-car-4/

Check with your car insurance provider that they will cover the modification to the car , not all insurance companies do .

Use of an A frame on the continent differs from country to country and ranges from You might get away with it, to Absolutely forbidden. The Club's advice for mainland Europe is to put your car on a trailer. 

Thanks all for your replies!

I have spoken to people while in France and Germany and they have been stopped by police and had to unhook the car being towed. I have this year bought a Smart and trailer and it works fine. Think how difficult it might be to sell on a car that has been modified. Trailer is the way forward.