Thanks everyone, and nice pics redwing - nice red setter there in 3rd pic.
If I read the council regulations right a carport can be more leniently positioned on a block than a garage, and also it seems able to be constructed in a wider choice of materials. That's why I wondered where the distinction lay. I want it as enclosed as possible but still called carport for council approval purposes. If you've had a quote recently for a garage you'll know why I'm asking! Whatever amount your thinking - it's higher than that!