the trailer-type you're asking about is called a Hybrid Travel Trailer. it's also sometimes called an "expandable".
it's called a hybrid because it's a cross between a popup and a travel trailer.
most of the vinyl canvas on these, have factory warranties of 6-7 years.
in my 6+ years of being on hybrid forums, i've never seen anyone that had to replace the vinylized canvas, because it got old. a tear or mice eating a section or kids damaging it, yes. but not for aging.
there is a Surveyor sub-section, in the Hybrid/Expandable Section, here on FRF. i suggest that you post any other questions there, since you'll find owners of that kind of RV.