Rube Goldberg Plastic Boat Storage

Being new to plastic boats, I have been concerned about deforming the hull through improper storage.  My concerns were heightened when I got minor deformation early on (which has since worked itself out).

I am sure most people with plastic boats don't go to the lengths to which I have gone to store their boats, but I was not sure what else to do.  The boat would be hard to fit in the garage, which is an oven during the summer anyway.  The only big enough climate controlled place is the living room, and I didn't even broach that subject with management.

I picked the shadiest, and therefore coolest, part of my yard and suspended the kayak between two trees.  I am sure the engineers among you will know why the boat refuses to hang level.  I know only that it does so.

Somebody tell me a better way.