Documents for Driving in Turkey
You should always have your vehicle registration, insurance policy, and national or international driver's license (or copies) in your car.
If there is an accident, you will need all three, as well as your passport or national identity card.
For rental cars, the rental agency will show you where the car's registration documents are. Provide them along with your driving license and passport or identity card at any Turkish police checkpoint.
— First-aid kit
— Reflective warning triangle
These should be included in the trunk/boot of your rental car, and the rental agent should point them out to you when you take delivery of the car.