Wasp
What happened i thought you said this thread was finished.
Anyway I'M BACK but I did leave my ball and ball behind so I can't play so i have to be serious, sorry!
So in case you are still thinking about it in my opinion the best option would be a couple of 4m long roller blinds hung from the eaves and long enough to be tied off on the rail (wall X) and the floor (wall Y) of the balcony. The blinds could be rolled up at night so you could see out the window to check on Grandma or once the sun moves north of the roofline (probably around March).
They can be secured to the eaves so they don't get stolen or sold. There would be sufficient "air gap" between them and the wall. I do not think they would be expensive and you would probably be able to get the seller to do the installation so you don't have to climb up to the eaves.
I am sure Missy could ask around and find a supplier easy enough. I have seen people selling them drive past our place so they may or may not be available at a shop.
Good luck with whatever you decide to do.
I'm outta here!!!