DIY retractable awning/shelter?
I am wanting to employ a canvas/tarp based shelter attached to the side of the bus - not so much an awning since it may end up being 30ft x 30 ft of tarp. I'd like a place to cook over a fire when it rains, without all of us getting wet. I'd also like something retractable if possible, ie with a roller that I hand crank, so I don't have to fold up a 30ft tarp. I'd envision either I tie the far ends to trees (with rope) or have posts that go into the ground.
I'm curious if anyone has developed such a contraption (similar retractable mechanism to an awning), maybe something welded or put together from odd/spare parts? The RV place down the road wants to sell a 17" awning for $300 and I'd rather fabricate one from tarp or canvas, with the right roller mechanism. Especially since I want/need something that is much larger than 17 feet x 8 feet (or however far it extends out).
I'd also like a setup that could adapt to a fully-enclosed shelter, and I'd prefer to be able to get all the materials from the hardware store - ie canvas/tarp, vinyl 'windows', square tube metal, etc... without spending $2000. This is supposed to be a survival thing anyway.
My other option is to do it all manually and have some fasteners under the top of the windows so rain doesn't leak through. But that adds complication to storage. It would be nice to be able to roll it up and tie it to the chassis framing rather than build an underside compartment to hold it.