Last year we bought a 12x12 Quest canopy, having been told that screens panels were available for it. They are not, and the 10' screens are $40 per panel, so we wouldn't buy them anyway at that price.
This year, at the local hardware store near where we camp, I saw screen rolls by ShelterLogic. They are quite robust and made to withstand the elements. We bought 3 rolls, 15'x6' each, which we will customize for our canopy. They were all of $19 apiece at Amazon. We are going to attach them with magnets, so easy off & on. At 6' high, they will not quite reach the ground, but bugs always get in anyway, and it's less to clean. We really just want the added bit of privacy and shelter from the rain. I think it totally beats the high cost of screen rooms.
2008 Forest River/Flagstaff M-205 Mac
2006 Toyota Sequoia