Sun shade for washing and waxing

My garage has great lighting but nothing like the sun. Usually, I'll wait for a cloudy day to wash my cars but humid days aren't good for waxing. I've been looking for a light weight tarp (18 X 24) that I could put up between my house and garage for shade. I contacted a sail maker in my area and he's going to give me a price. I'm sure it won't be cheap. I can find lots of tarps on the net but they're colored and I'd like something that just provides shade, preferably WHITE with eyelets. Ideally, it would be made out of light weight nylon or something similar. Any suggestions would be appreciated.

Here in ranch country there are several Tarp companies that will make you a tarp according to your specs. Some of the hay tarps are really nice and could be applicable to your situation. Another consideration is to design it like those awnings on the side of some camp trailers and motor homes that just lean out from the side and then you can lean them back into place and out of the way when you are through.