Hmm potentially although I suspect I couldn't reach to the back of it. Definitely not to do the alternating coloured panels I initially wanted but maybe with a roller on a pole....thanks for your suggestion, will look into it!

I would choose a light, warm colour for the walls. If you are uncertain what to use, you can pay for a colour consultant will go to your house to put forward their recommendations. According to their website, Dulux charges $150 for this service. I think it's worth that amount if undecided on colour. I love plantation shutters, however, with the extra large windows and doors in your house it would cost a lot to install them. Alternatively you could use layered curtains or insulated curtains. Use heavy fabrics or layered curtains over the windows to keep out drafts. Or, purchase insulated curtains with built-in thermal backing. Window pelmets are also good for keeping out the cold.

Thank you for your reply bigreader. I did contact a couple of whirlybird companies and they did confirm 2 to 3 wind-driven whirlybirds are suitable for a roof of that size. I will use those instead of a single flume vent for the outlets but what about the inlets? Soffit vents require several holes to be cut into the soffit for adequate ventilation and can let insects into the roof cavity. Over fascia vents don't but it seems that they are not yet available in Australia. Does anyone use anything other than soffit vents?

A standard garage should be 6m x 6m. This allows room for all types of vehicles, unless you own a F250 or a chev Silverado. It allows for doors to be opened and access completely around vehicles, and room for storage if required. We have a 7.5m x 6m garage. We have a pull out clothes line, a spare fridge when required for gatherings, storage, and Ford Ranger which is 5700mm long. So in answer to your question, a garage should be as big as you require it to be, and as big as the building block allows.