Transport
In Nice
For Nice itself a car can be a hindrance. Parking is not easy and not practical especially in Vieux Nice. If you are fit, cycle, using a Bike-share Bike, or just walk. Failing that there is a good and cheap Ligne d'Azur bus service and also the modern tramway which goes from the North west of the city to the north east via the Place Masséna in the centre. Taxis can be expensive.
Outside Nice
If you intend to explore the Côte d’Azur either side of Nice then either use the bus or the train.
A car is useful but expect very heavy traffic especially east of Nice and parking can be difficult. However, while there is a bus service into Nice Beyond and the Parc National du Mercantour, the best method of exploring this region is by car.