If your holiday in Marseille is going to be focussed on relaxing on the beach in between wandering through the many shops on offer, then a car is of little use, and the excellent public transport and the taxis will be more than adequate, however if you plan to tour the region inland from the city, or spend time travelling along the coast as far as Nice or Monte Carlo, then hiring a car in Marseille is essential, and can be done prior to travel quite cheaply, although you should ensure that the package that you buy includes all the appropriate insurance and taxes, otherwise you will have a large bill to pay on arrival.
