Stayed in Cassis (beautiful town!), took the tourist boat to the rocks, climbed all day, and got the boat to pick us up at the end of the day. If you do it this way, you can keep your car at the hotel (most of which have locked indoor garages). The climbing was excellent!
Unfortunately also experienced some idiot broke into my Citroen 2CV by cracking glas. Certainly no professional, since he did only steal old clothes and he just could have ripped the (textile) roof of that car for much easier access... ;-(
Anyhow, great area to climb, just better leave your car unlocked or simply fly to Marseille.