Just starting to "engineer" (LOL) this project. I originally was going with a tarp, but realized that when draped down the top roof sections, the sides would be on the low side with a tarp big enough to go from one side to the other. Researched "waterproof shade sails". Found a 10' triangle with an additional "D" ring in the middle on one side. ( 40 bucks on Etsy). I just finished installing a bracket to hold the middle "D" ring at the top. The other ends on the camper side will be attached with either sturdy bungees or ratchet straps. The top outer point will be supported by a 9' tent pole from Cabela's. It has a neat hand lever to stop the pole at the height you need. A guy rope will be attached to the top pin and run down to a 10" tent stake (or a screw in type for sandy soil). Hoping that it will give just enough protection for the front door area in rainy weather. Won't be as effective as a canopy attached to a pop-up roof, but should help some. The top bracket is an aluminum L bracket for screen porch construction. (See pic). Was a left-over from a previous project and I like it better than bending a washer. and.. it already had holes drilled in it. The top screw and wing nut will grab the "D" ring of the sail at the top and bring up the shade sail with the roof when setting up. Or...at least...that's the plan! Will post pics of the canopy when in place for use.