Carrying someoneelse bike into turkey
 

Ciao, any traveller can tell me if it is possible for me to carry into Turkey border, coming from Greece, my car and trailers with my friend's bike who are coming by plane to Istanbul?
I know that if you cross border with turkey with a bike which is not yours,you need the owner permission stamped by a notary and traduced.
But in this case?
Motorcycles are italian, car, trailers me and friends also.
Thanks!! Ciao