Best waterproof deck covering?

I think I’m going to renovate my deck this summer. It will have to be plywood covered with something waterproof since there’s a carport underneath. Should I use a sheet vinyl product, or do they have roll-on stuff that’s good? People have been telling me to get a shade saile (www.shadepundit.com). I found a lot of reviews online but still don’t know which one to go for. Does anyone have similar experiences? I’ve been looking at this shade sail review, which is about $50,any advice would be great.