Do I need a car to reach the small towns in Provence if I start in Arles? Are there buses to these places?
A car is a good idea, and a must if you want to get to the small towns.
You don't need one for your whole trip, just to explore the countryside.
Some towns have bus service, but many don't and the service can be infrequent. A lot depends upon which towns you want to visit, but a car is usually your best choice.
Not only is a car you best bet because bus service is laughable, but because it is the drive itself which is stunning to see in Provence, especially if you head over to the Alpes-Maritime. The back winding roads have some beautiful scenery, tiny villagettes, and road side honey stands. In a car it is easier to stop and explore or an impromtu pique-nique.
You live in Punta Gorda ha, ha, I used to live in Virgin Gorda.
We recently returned from Arles where we used a car for a few days to see smaller towns, then used train before and after to see some of the more accessible locations.
Since it was winter, the bus schedules to the smaller towns were quite infrequent, but moreover, did not get us to the towns/order in which we wanted to see. Nor could you stop and explore.
For us, the couple hundred bucks was well spent, plus we were able to pick up in Avignon and return to Arles, making our train connections a breeze.