As mentioned we allow to visit every European country with our VW camper vans. We are also talking about countries outside of European union like Serbia, Kosovo, Albania and more.
We even had a renter who took our old school camper on a 2 month journey through Turkey. So yes - Turkey is allowed too, if you have enough time to do it.
Important document when traveling to these countries is green card. It is internationally recognised insurance document which provide proof of insurance cover to law enforcement agencies. It satisfies the police in the country visited that the renter has the minimum compulsory insurance cover required.
Green card is aready included in every camper we have, so you can cross every border with out a problem.