As per RTA, all rental cars in the UAE are provided with comprehensive insurance (a.k.a. basic insurance).
This means that by default, you are covered incase of an accidental damage provided it isn’t your fault.
A police report must be obtained at the time of an accident. Your rental amount includes basic coverage.
Most car rental companies provide CDW (collision damage waiver) for an additional charge.
This covers you for any accidental damage by your own fault as well. However, a valid police report is still required for coverage.