After many hours of shopping for shade sails, I found the best price for this size(18x18) here on Amazon. I received it promptly, and when I opened the Amazon shipping box, I found the shade neatly folded in a clear plastic package. Similar to what a comforter set comes in. It also had some rope, and unfortunately, no instructions.
I found other resources for install instructions and there is a lot of info out there. It took me a month to finally install it because I over analyze and questioned the installation over and over. I finally made the decision to install it off my patio roof on one side and a pair of steel pipes on the other side of the pool. The pipes were 13' each of 3.5" Schedule 40 black steel. I found these locally for $78(for both). That was an awesome find on Craigslist. Steel suppliers wanted $300-400 for the pair!
These pipes are in holes that are 4' deep and about 20" wide filled with concrete. That was a lot of work, and 20 bags of 80# concrete. Suffice to say the pipes aren't moving.
On the patio roof side, I used 8" eye bolts in holes drilled through the 4x4 header beam. I used large washers on the eye side of the bolt, and 3x6 piece of steel plate on the back side of the beam. This was extra insurance to help spread the load on the back of the beam where it would have the most pressure when the shade is tensioned.
I suspended the shade from the mounting points with chains and used turnbuckles on one side for easy tension adjustments. Total parts cost including the shade was $350. Not bad, but the cost of the steel can easily double the cost.
I am super happy with the shade sail now that it is installed and it's holding up very well. The quality is equal to Coolaroo and others with heavy duty stitching and steel connections on each corner. I would have given this 5 stars had it came with instructions, a support number, something!