Iceland is expensive! Cooking your own meals saves money on your holiday budget, and you are allowed to bring in up to 10 kg of food per person. No one checked this, nor did they check the amount of alcohol we brought along.
Due to the bad weather, we often cooked in the campsites' communal kitchens – which was a great way to socialize.
The Campingcard secured us a few affordable nights. However, you shouldn't expect too much from the campsites; the sanitary facilities are almost always far too small for the number of guests. Usually we went to the municipal swimming pools to shower.
By the way, you can check up-to-date road information at "umferdin.is".
And if you are traveling for longer than 30 days, you will automatically receive an email—after booking the ferry and about a month before departure—detailing which forms need to be filled out online.
We drove 5,744 km across Iceland in 43 days :-)