Also, does the wing have to be renewed after a certain time?
UV can drasticly reduce its lifetime.
My Mainair Flash 2 wing finally failed it's annual Betts test after 16 years and 1,100 hours, which I think was pretty good all things considered. Cost me £2,200 for a new sail and rebuild. I often used to leave it outside for several days in a row if the weather was fine, and it would be getting the sun all day. I remember reading that tests have shown leaving one out in the Sahara desert would terminally age it in just 3 months!
The manufacturer says it's best to keep them fully de-rigged in the "Bag", but it's so easy to tear the fabric or crease a cable doing this that I prefer to keep the wing fully rigged and just remove it from the trike for storage. This only takes 10-15 minutes, as against at least 45 minutes (with some help lifting) to fully de-rig.