In reply to olliee:
You really don't have to pay £40 or whatever to park in Oban for the week, but if you want to be sure about your van it is probably slightly safer in a paid for car park.
There are plenty of streets 15/20 minutes walk from the ferry terminal where you can leave your car for free. Get there early and drive around and you'll quickly find somewhere.
My advice for Pabbay also around ropes - don't let other people use your ropes. One of ours was trashed by another party who refused to take any responsibility for what they had done, dismissing our concerns with a "just tie a knot in it". Every team should be self sufficient.