Hi Killametre,
I purchased a Rooftop Campers 2.5 meter side awning from Ebay for $245 delivered. This is a great awning at a fraction of the price of the big name brands. I have used it in all types of weather with no problems. Very easy to setup and pack up. You can use it without the separately supplied support ropes but if there is a gust of wind it could flip over the top of the car and cause some damage so I always use the ropes as insurance.
The awning comes with mounting brackets so all you need is either a cargo rack or two roof racks to mount the brackets to. This is now I did it before I got the cargo rack.
Paste the link below into your browser to see the awning on Ebay.
Hope this helps.
http://www.ebay.com.au/itm/MANUAL-RE...item1c24c4de95